Everybody at the table seems competent at least. No reads other than no one has gotten crazy or overaggressive at all. Haven't seen anything tricky either. Not sure what the best play on the flop was, but I was seriously considering a push if UTG went away on the turn, given what I thought SB's hand range could be.

PokerStars No-Limit Hold'em, $1.00 BB (6 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

BB ($173.40)
UTG ($91.50)
MP ($99.75)
Hero ($94.45)
Button ($105.40)
SB ($102.50)

Preflop: Hero is CO with T, 9.
UTG raises to $3, 1 fold, Hero calls $3, 1 fold, SB calls $2.50, BB calls $2.

Flop: ($12) T, Q, 9 (4 players)
SB checks, BB bets $10, UTG calls $10, Hero calls $10, SB folds.

Turn: ($42) 5 (3 players)
BB bets $35, UTG raises to $78.5, Hero folds, BB calls $43.50.

River: ($199) 2 (2 players)

Final Pot: $199

I'm fine with the hand, sometimes I'll raise this flop especially in position and to control the pot as it's likely checked to me on the turn. Folding the turn is standard as played.

I completely agree.

What won?

I had a hand not too long ago that was quite similar to that. I flopped the nut straight though on a flush board and donked my stack away even though the my villain pretty much laid it out like your villain did. I guess I live and learn.

If you read your opponents for competence, I would say folding on the flop is not the worst decision in the world there. That's just too terrible a board texture for bottom two. You can always fold and wait for a better spot.

Folding the flop here would be quite bad considering we have position in the hand and can get away from any aggression cheaply. Your line is fine donk slayer although raising the flop would give you a better indication of "where your at" your logic regarding UTG's call is fine and i dont mind just calling here to see what develops. Turn fold is standard. NH.