SB has reasonable stats after small sample. Low WWSF but av AF.

Can't really call riv bet so just fold now?

PokerStars - $0.50 PL Hi FAST (6 max) - Omaha Hi - 6 players
Hand converted by PokerTracker 4

BTN: $83.74 (VPIP: 27.66, PFR: 14.89, 3Bet Preflop: 8.70, Hands: 48)
SB: $145.19 (VPIP: 22.97, PFR: 17.57, 3Bet Preflop: 9.52, Hands: 77)
BB: $45.10 (VPIP: 20.26, PFR: 13.07, 3Bet Preflop: 0.00, Hands: 160)
UTG: $91.41 (VPIP: 23.48, PFR: 15.85, 3Bet Preflop: 7.32, Hands: 333)
MP: $74.65 (VPIP: 26.42, PFR: 16.98, 3Bet Preflop: 7.41, Hands: 54)
Hero (CO): $103.43

SB posts SB $0.25, BB posts BB $0.50

Pre Flop: (pot: $0.75) Hero has 4 9 Q J

fold, fold, Hero raises to $1.50, fold, SB raises to $5.00, fold, Hero calls $3.50

Flop: ($10.50, 2 players) 3 A T
SB bets $6.00, Hero calls $6.00

Turn: ($22.50, 2 players) 9
SB bets $14.00, Hero?

I would likely call turn aswell, as I think he would bet/bet with set along with flushes, possibly even nfd blockers but that we dont know yet. So calling and see if he slows down on river. Would probably call down with Q high flush and see what he shows up with.

I call again, decide on the river.
If you fold this you are kinda folding your whole range except nuts and 2nd nuts.

Having trouble understanding why it's more important to consider hero's range than villain's range, I guess I understand why it's more important to do so at midstakes but I would have assumed at 25PLO (esp. zoom), it's more important to consider villain's range, and then hero's perceived range.... Could you elaborate? Thanks

That's a very good question, and to be honest you are probably right that staying balanced might not be the top priority at lower stakes (this is zoom50 btw not 25 but it doesnt really matter). However, I think that every person who is trying to work on their game, improve and eventually move up has to take such things as exploitability of their range into consideration.
As far as this particular spot goes, since we are not given any reads on the villain we should play this spot as optimal as we can from a theoretical point of view. And from that perspective this hand is very close to the top of our range, thus we can't fold it on the turn.
As far as river goes, we will have to see what villain does, but if he bets big it becomes a very close spot and I would probably lean towards folding readless.

That makes a lot of sense And when you say we should play this spot optimally, do you mean gto optimal or the most +ev play (readless and/or with the limited reads we currently have)?

GTO and the most +ev play is the same thing if we are readless