Ugh.
The dealer ought to have immediately asked the whisperer to clarify his or her intention. If the hand was actually tabled, then Rule 48 would not apply, but rather Rule 15 would. And that's the question I suppose... was the hand actually tabled.
winning hand was AK and was tabled, and the player with AK first whispered "call" or "fold" then turned AK face up on the table, then reach for his chips.
When I asked "what did you say mr?" he said "I said call" and some players didn't understand the word, so did the dealer...
If it really happened this quickly
before all the cards were mucked, then there is no issue, is there? The call has been clarified and the showdown continues. However, if this only happened after the cards were mucked, what I want to know is: why in the time it took the muck the hand did the whisperer not move his chips in (perhaps he did?) why did he not speak up when the dealer took his AK cards to muck them? did the dealer tell the opponent that it was a fold, and why did the whisperer not chime in to correct this? AND how was the opponent so sure it was a fold, rather than a call or a raise?
This is very situational. With the action being bet, raise, (?), I think it is reasonable to assume that there are enough cases that a call would be expected, especially if it was reasonable given the board. While this is not, in itself, conclusive, it is relevant since IMO
the opponent (player 2) also has an obligation to protect his own hand by verifying whether the whisper has actually called or folded before mucking his own hand face down. If he mucked his hand face down without taking any steps to verify whether the shown hand was a call (particularly if he can see the player reaching for chips), a fold, or perhaps even a raise (!) or even an "I'll show you my hand to see your reaction but I haven't acted yet" move,
all of which are plausible situations, then the opponent has failed to protect his own hand. It is true that turning one's hand face up does not necessarily indicate a call, but both players bear responsibility for identifying what the action means and to proceed accordingly.
So yes, the whisperer must make his intentions clear, but the dealer is also at fault for not immediately asking for clarification, and the opponent is also at fault for not seeking clarification himself before potentially folding the only hand that has not been tabled. It should not be so easy for dealers to kill hands that have been turned face-up by saying "well you might have said call, but I didn't hear it/you didn't say it loud enough/I'm going to pretend I didn't hear it/I'm racist and I hate your accent/I don't like you anyways/etc., so I'm killing your hand". I think I would have to be at the table to feel comfortable with any decision, but I personally do put significant weight on the fact that at the very least, the whisperer's hand is an exposed hand and the action is ambiguous: therefore, the opponent should have taken steps to clarify what the action was before allowing his hand to be mucked face down - so I would tend to award the pot to the only player with the tabled hand on that basis more often than not.