I would have kept the pot as small as possible when the flop didn't help your hand and it was three way. Probably checking behind on the flop and then betting out about 2/3rds of the pot if they both checked again to you on the turn, just to see if I can pick it up.

That being said it's hard for you to stick in 21k there, but from the description of the guy a fearless pro like a Barry Greenstein or Mike Matusow would have stuck all their chips in.