I know he had at least one other extremely egregious flop against Yao earlier in the year. Might have been the second game they played in Houston.
I actually like Joel Pryzbilla a lot. I'd love him as a backup C on my team. But he has to be near the top of the list of worst post defense floppers. Varaejo is king, Oberto is pretty good, but Pryzbilla is right there as well. And, yes, Scola does flop. But he's Argentinian and has played in Europe, so he has an excuse.
What I was referring to (25 seconds in). And Scola comes back with a flop of his own ... though at least he wait for the contact before he started falling down. There is an art to flopping correctly!