The determinism dilemma is that if our actions are predetermined they are not free, and if they are random they are not willed, either way there is no free will. Even if will causation is a mixture of chance and necessity it can be split into the corresponding aspects according to an argument that goes back to Hobbes, reinstating the dilemma: "in order to make the causation somehow indeterministic, a realization of a random variable (completely uncaused and independent) would have to be put amongst the conditions." To put it metaphorically, we are puppets dangling on the strings of causality, or chance, or both part time.
A popular response is the two stage model of free will, where at the first stage actionable alternatives are "freely" generated, and at the second the one that "best" suits our goals and desiresis "willed". Trouble is that the "free" stage is not willed, the "will" stage is not free, and the freedom itself is reduced to imperfection, inability to survey all possible alternatives. Although the model itself is relatively uncontroversial (both Dennett and Kane accept it!) it concedes the Hobbesian split into chance and necessity, and merely shifts the dilemma to the second stage.
But we know of at least one type of processes, where the Hobbesian split can not be accomplished, quantum evolutions. I am not suggesting quantum mechanics as a physical model of volition (but such suggestions were made, by Compton using macroscopic amplification of quantum effects, and Penrose using hypothetical "quantum gravity"), or even saying that it is a "complete" description of reality. But it is a model where the wave function "is all there is" by definition, and it is self-consistent if set theory is.
The wave function is neither deterministic, nor random, nor a "mixture" of the two (see Bell's inequalities). We get a model for events that provably can not be split into a mixture of chance and necessity along the Hobbesian lines envisioned by the dilemma. Free will does not have to operate anything like quantum evolution of course, the point is that combinations of chance and necessity do not exhaust logical possibilities, the two can be entangled in unsplittable ways.
Is the determinism dilemma a false dichotomy? Were non chance/necessity options explored by philosophers as models of how free will might operate? Specifically, how "goals and desires" can be factored into volition without resorting to partial causation?