How should I have played this?

In MTT top 2 cash down to 11 (two tables running) Final table of 10 will convene when next player is eliminated.
Blinds 300-600.

UTG (13800)
UTG+1 (18000) - HERO
CO (10000)
Button (17000)
SB (6500)
BB (1300)

UTG raises to 1200, I call with Ah Jh, everyone folds to BB
who moves all-in which was a raise of another 100. UTG and I both call the extra 100. Preflop Pot (4200)

Flop comes 4h-9c-9h....UTG raises all-in for remaining 12500 in chips. I think for a bit putting him on hands ranging from overcards to medium pocket pair to possible A-low. Opponent had been fairly loose trying to steal pots. I felt like I could catch a jack or hit the flush and win the pot. So I felt like I had 12 outs. Pot (16700) so I was getting 1.3 to 1 to call. I felt like I was around a 3 to 2 dog and if I won the hand would be the overwhelming chip leader with almost twice as many chips as 2nd heading into the final 10. I decided to gamble and take a little to the worse of it and try to hit my hand. The UTG player flips up 8-9 off and his trip nines held up. How bad a play was this and should I have played the hand differently.
I had been very tight prior to playing this hand, while my opponents had been stabbing around trying to steal pots.