[Probability]

OK this guy is weird and makes some unorthodox plays. I raise 2 limpers preflop and the both come along. The second guy donks the flop small and I pop him up with overs and a FD. The villain ck min raises. He is repping a very small range here, 33 A3 66 or a limped over pair (he is 29/16). I flat the cmr and turn the flush, he leads for 100 into 167 and I am scared. I elect to flat again, I feel I am most likely behind at this point. On the river he bets 180 into 370 and leaves 50 effective behind. I am not folding, the question is to get the last 50 in of not. He cant fold anything at this point so I get paid by JJ+ (if he slowplayed pre), A3 (makes more sense than a PP), a lower flush. I get stacked by 45dd, 66, 33, Axdd. I decide to flat and feel like a pus. Anyone do anything different?

BB ($187.10)
UTG ($421.50)
MP ($109.20)
Hero ($410)
Button ($226.30)
SB ($476.73)

Preflop: Hero is CO with Kd, Qd.
UTG calls $2, MP calls $2, Hero raises to $8, 3 folds, UTG calls $6, MP calls $6.

Flop: ($27) 3d, 3h, 6d (3 players)
UTG checks, MP bets $6, Hero raises to $34, UTG raises to $68, MP folds, Hero calls $34.

Turn: ($169) 7d (2 players)
UTG bets $100, Hero calls $100.

River: ($369) 2s (2 players)
UTG bets $182, Hero calls $182.

Final Pot: $733