linker split,
I think Stuart answered your question correctly. I am a little confused as to how many players were in the hand at the end. You mention that Player 1 checked and player 2 (in his opinion) didn't act. There is no mention of Player 3? If only two players were in the hand, I would have to assume that the dealer thought that the player also checked (by a jesture, or action). If there were three players, then you could assume that the player, (for any number of reasons) was missed by the dealer. In any event, like Stuart said, a tap and burn by the dealer is plenty of time for the player to speak-up and let the players and the dealer know that he is in the hand. Changing the turn or river card, is out of the question.