No because the human doesn't expect that he might be talking to a machine. If he knew there was a 50% chance it was a machine then he'd find ways to recognize it - like its inability to follow the conversation at all.
> ...he states only that player A is to be replaced with a machine, not that player C is to be made aware of this replacement.
[1]: https://en.wikipedia.org/wiki/Turing_test#Should_the_interro...