He was sitting in 2nd in chips, with over 20 million and made a classic pressure raise, bumping it from an early position with 5-3 diamonds. Nothing wrong so far. He got one caller, from a blind -- Darwin Moon, the chip leader, who was the only guy at the table who had him covered.
Flop hits K high, and three diamonds. Both players check.
Turn hits the two of hearts, pairing the board. Moon checks. Kopp bets out 2 million... and Moon check-raises to 6 million.
Now, if you're Kopp, what should your thought process be here? You flopped the baby flush, but Moon is showing some kind of strength. Maybe he has the ace of diamonds. Maybe he has a two and made trips, or something like off king-queen (or jack, or 10) of diamonds. Lots of hands that could catch up on the river. Or maybe he flopped a mediocre flush of his own. Less likely, maybe he flopped the nut flush, or hit two pair or trips on the flop, and you're now drawing dead.
Most importantly, what you should be thinking is, "This is the one guy at the table I do not want to get balls-deep with, because he's the only guy who can bust me out."
Kopp apparently never got around to that last thought.
He responded to Moon's raise by re-raising all-in. Moon called, showed QJ of diamonds, and Kopp was done.
Dude, you were three eliminations from the final table, and in great chip position. Maybe you just call the raise; possibly you come back over the top with a smallish re-raise of your own (although 'smallish', in this case, would have meant a bump to 9 or 10 million).
The absolute last thing you should be doing is pushing all your chips into the middle, against the one person with enough chips to actually call, when there is a decent chance you could be drawing stone dead.