Objective reality exist independently of the perception of discrete sentient beings. It doesn't rely on or mandate the existence of such beings whatsoever.
Is Objective Reality really just the Subjective Agreement of a given
It is at best "perceptual consensus". Subjective reality is just a subset of objective reality, distorted and limited by a finite and usually flawed perception. Therefore, it doesn't exist outside a particular mind, making it entirely imaginary. And you cannot call something imaginary a "reality" because the two are complete opposites.
Is the 1 person out of 100 definitely "wrong" about what reality it?
The beliefs of the majority at best define the status quo.
And the status quo is not guaranteed to be neither right nor reality defining.
looking back at every previous status quo belief, there is not a single case of one being correct. They have been proven wrong and abandoned time after time. And there is absolutely no reason to assume the current one finally got things right. Surely, it might be more convincing than the previous ones, but I reckon the same applied to every previous one as well. So no, the majority is not necessarily right
there are many cases in which the 1% introduced social doctrines that were largely accepted by the 99% without defining reality according to them. For example religion trained people to be obedient with the belief that god will reward them for it, while also punishing the wicked. And the 99% believed that, however that belief never defined reality according to it. Good people were trampled on and bad people got their golden ticked to capitalize on it. So no, the majority does not mentally define reality. On the contrary, the majority is exploited to physically redefine reality into a form that is more beneficial to the minority.
Hopes, deceptions and illusions exist in the mind, they are imaginary, and as such have no effect on reality. They do however condition the population to be harnessed into physically altering reality, usually in the completely opposite direction.
The subjective is subjective, and adding more subjective to it doesn't change that, there is no tipping point in which it magically turns into objective. It is not something that can be enforced or agreed upon, it is absolute and universal and is not subject to the beliefs or delusions of its creations. We can alter it physically to a degree, but the way we see it or are being made to see it in no way affects what it is on its own.
You can raise Johnny in isolation and teach him that EM radiation with wavelength of 700 nm corresponds to the color green rather than red, and one day Johnny might park "his green" car next to Larry's red car, and all of their coworkers might agree that Johnny's car is red too, but for everyone both cars will have the exact same color, reality won't bend and snap to produce a tangible difference, because the color itself, as a product of objective reality is absolute, regardless of what words different people might use for color, light, frequency, wavelength, units or numbers of measurement.
If you put 100 people on an island, and poke the eyes of 99 of them, the world won't turn dark for the one that retains his sight just because the majority has lost it.
99.99% of the people cannot last 5 minutes under water, and perceive and agree on that fact, but that doesn't define a reality in which no one can.
I can go on and on, the point is there is plenty of obvious observation to answer your questions, but still:
1) Is any definition of objective reality really just a democracy or
vote which is relying on the most popular perception?
No, it isn't. Whether it is smart people agreeing on empirical evidence to forge intelligent theories, or it is idiots collectively fooling themselves with something convenient and reassuring, it doesn't affect objective reality whatsoever. It only affects our perception of it. And what we perceive is defined by objective reality, refracted through our subjective and imperfect minds. Not the other way around - that would mean we are necessary as precursors to reality, and there is ample evidence reality existed long before us and was the framework of what eventually resulted in our existence.
2) If #1 is true, doesn't this just mean that reality is truly
subjective, just there may be larger and smaller populations of people
that basically agree on the same nature of reality?
3) If #1 is false, then how can it be explained that ideas like logic,
empirical data from the 5 senses, the scientific method, and any other
basis used to determine objective reality is true outside of an
individual's perception of both these ideas and the other observers
needed to verify them?
Those things just allow us to communicate. It just gives common things common identifiers so different people can understand what they are saying. We don't invent laws of physics, we only come up with approximating descriptions of what we discover is already at play. Those things do not determine objective reality, they merely attempt to approximately describe and quantify it.
It doesn't have to be democratic either, the way it usually works is a single individual discovers it and gets to name it, then tells it to someone else referring to it the way he conceived. It sometimes happens that things are discovered independently by different groups of people, leading to different names for different groups, when those groups interact sometimes both terms apply, but usually the more popular eventually prevails. But that's just how the brain works, if 1 is refereed to as A more often than B, then over time that's what grows on you. It has nothing to do with objective reality, it is still entirely in the mind.
I for one don't recall anyone calling general elections to define what words we use to describe certain aspects of reality. In fact it is usually a minority that defines those things for us without asking us at all, at least when it comes to official nomenclature. Slang can be different, it is sometimes spread through popular usage, although quite often a few popular or influential public figures play a key role in spreading it. We are after all just primates. Monkey see monkey do.
Last but not least, democracy in translation means "people's rule". What a minority fooled the majority into believing to be democracy is actually a blatant mockery of both true democracy and our very right to chose. Obviously, even if most people believe it to be democracy, that didn't result in a reality where it really is democracy. It is still a bunch of mindless cattle getting to chose its butcher every few years, the option to not have a butcher or not be cattle is not even on the table. I mean the moment they say that the vote of a firefighter or a professor has the same weight as that of a drunken hick living on welfare it should rise a big tall red flag. And of course, we never got to democratically vote what democracy is either, but the words are still translatable without any room for ambiguity as of what they mean, for those who are interest in objective reality rather than subjective illusions ;)
Wouldn't it be swell tho, if we could all just come together and solve all our problems simply by agreeing we don't have them.