Rules Scenario Debate

[Warik]

This came up at the local indian casino last night.

Heads up SB vs. Button on the river

SB bets $2.
Button raises to $4.
SB raises $6 and flips his cards prematurely showing a baby boat - threes full.

Button knows he has the nuts (kings full) and flips his cowboys.

SB immediately goes nuts and says "NO... YOU FOLDED. YOU DIDN'T CALL MY BET, YOU FOLDED."

Everybody including the dealer looks confused and then everybody on the table's confusion turns to anger against the whiner.

"You flipped your cards early, he knew he had you beat."

"NO! HE FOLDED. HE DIDN'T CALL MY BET"

"You didn't give him a chance to. You flipped your cards early before he could do anything."

"HE DIDN'T CALL IT. IT'S A FOLD."

"I didn't fold! I turned my cards over. I have kings full! Why would I fold that?"

Dealer calls the supervisor over.

After much debate SB insists that they split the pot and they eventually do... which I thought was BS and unfair.

So... who is entitled to the pot?