All we need to assume is that Photekq won’t change his bidding in response to the other person’s answer.
If the other person decides, in response to Photekq’s maximum bid, to increase her own maximum bid, then Photekq might not win an auction that he otherwise would have. However, the winner will still be the high bidder, so I don’t really see the problem. I suspect Photekq would be slightly disappointed but not upset in that case.
Overall, I think you’re grasping at straws. Photekq’s plea on this thread is +EV in almost every circumstance, and you need to hunt for weird pathological cases to find a case where it hurts him.