I think I made a mistake by not cBetting on the Flop (I don't play PLO that much).

How much should I cbet on the dry flop in multiway 4bet pot?

3bettor's "3Bet Preflop" is 14 and VPIP 81, very loose

iPoker - €0.04 PL Hi (6 max) - Omaha Hi - 5 players
Hand converted by PokerTracker 4: http://www.pokertracker.com

BTN: 39 BB
SB: 172.25 BB
Hero (BB): 103.75 BB
UTG: 81 BB
CO: 95.25 BB

SB posts SB 0.5 BB, Hero posts BB 1 BB

Pre Flop: (pot: 1.5 BB) Hero has Ah 3d Th Ad
fold, CO raises to 2 BB, fold, SB raises to 4 BB, Hero raises to 14 BB, CO calls 12 BB, SB calls 10 BB

Flop : (42 BB, 3 players) Tc 7d 5h
SB checks, Hero checks, CO checks

Turn : (42 BB, 3 players) Qs
SB bets 29.25 BB, fold, fold

SB wins 39.25 BB