50nl tptk 150bb deep vs fish and unknown

SB is a 64/23 over 64 hands. overvalues pairs and plays bad in general. MP2 is 53/27 over just 15 hands. in a prior hand he 2x 3bet my MP open (so it wasnt a misclick) from the BU with 99. he bought in for 200bb (didnt win his deep stack) and topped up $10 after he lost the pot he min 3bet me in. during the play of the hand i had the impression he was a similar type of drooler but i can't remember any specific hands, i probably just made the judement based on his 2x 3bet in the earlier hand. bad sizing, bad 3betting range, probably a bad player. i smooth the droolers lead because the board is dry as hell and i want MP2 to keep his Ax hands if he has them. i do not need to protect my hand against draws. due to a lack of reads i do not know what i am being minraised by. as a guess A9+, 22,88,A2,A8. i'm lost as to what the optimal play is here on the turn. thoughts?

Absolute/UB Cereus No-Limit Hold'em, $0.50 BB (8 handed) - Absolute/UB Cereus Converter Tool from FlopTurnRiver.com
Button ($91.55)
SB ($24.38)
BB ($49.50)
Hero (UTG) ($72.55)
UTG+1 ($21.10)
MP1 ($49.25)
MP2 ($112.60)
CO ($23.25)
Preflop: Hero is UTG with A, K
Hero bets $1.50, 1 fold, MP1 calls $1.50, MP2 calls $1.50, 2 folds, SB calls $1.25, BB calls $1
Flop: ($7.50) A, 2, 8 (5 players)
SB bets $7.50, 1 fold, Hero calls $7.50, 1 fold, MP2 raises to $16, SB calls $8.50, Hero ? (roughly $60 effectives, pot $47)

I'm not worried about the small blind, and if MP2 is not a reg then you can't fold

you're right. the small blind was never a concern because he's only 50ish deep and an utter fish. i assume once the pot is this bloated and about to be partially locked up we want to get the rest in, am i better off jamming on the flop or smoothing and getting the rest in on a later street?