BTN: 812.74 BB (VPIP: 24.64, PFR: 14.49, 3Bet Preflop: 0.00, Hands: 70)
SB: 100 BB (VPIP: 22.78, PFR: 18.89, 3Bet Preflop: 7.87, Hands: 1,045)
Hero (BB): 100 BB
UTG: 100 BB (VPIP: 20.47, PFR: 14.95, 3Bet Preflop: 8.70, Hands: 220)
MP: 56.1 BB (VPIP: 16.18, PFR: 8.82, 3Bet Preflop: 0.00, Hands: 70)
CO: 104.3 BB (VPIP: 23.55, PFR: 19.16, 3Bet Preflop: 9.68, Hands: 584)

His stats are pretty passive, so folding is probably best unless we have reads/history or we want to gamble.

noone can tell you what to do without more info

Like unexploitably you should call 51% of your range here at least
I assume you want to be tighter than optimal tho when he 3x BU and uses these sizings
and also that oop when he cbets 3way you won't peel flop as often vs them odds.

If you flat KQ pre you can fold be very happy about it call KQ. If KJ it's the strongest king you have it's closer but I'd still muck at NL50 because people rarely bomb all streets 3way without rly liking their hand