I thought an important feature of the Turing test was that the situation was exactly equal for each contestants, human and computer. The interrogator communicates with each using a teleprinter. Turing in his 1950 paper when talking about the interrogator communicating with player A in the imitation game: "The ideal arrangement is to have a teleprinter communicating between the two rooms [interrogator's and player A's]" then in the next para: "We now ask the question, 'What will happen when a machine takes the part of A in this game?'".
So there's one teleprinter in the human's room and another in the computer's room, and the interrogator types the questions on their teleprinter and gets printed responses back from the contestants. Everything is equal except one contestant is a human and the other a machine.
But the computing machine has no sensory apparatus. It can't see the questions printed by the teleprinter in the computer's room. If it can't see the questions then it can't understand them. In fact the computer must be wired directly into the interrogator's teleprinter, and the computer gets voltages - not words. The computer might have its causality defined by a human programmer (by programming the computer) such that the computer sends voltages back to the interrogator's teleprinter and words are then printed by it, but still, the computer gets voltages, not words.
Since the causality of the computer is defined by the human programmer, doesn't that mean that the Turing test, as Turing describes it, actually tests the intelligence of two humans, the human contestant and the computer programmer?