7 handed. 5/5 No Limit 200-1K buyin. Hero bought in for 700 b/c that covered all the player against whome I felt I had a significant edge.
Hero is playing somewhere between Laggy and Taggy--internet VPIP numbers would put me at LAG, but live LAGs are often looser than that.

Hero has been successful for the past hour with what I joke with my friend is: "creativity." Raise preflop + c-bet. Or, slightly more exciting, a couple times I called the preflop raise from another player and donkled. One pot I c-bet, was called by a rock who I know well, the other lag folded, and we checked down turn/river (i flopped middle pair, he flopped top pair--both shown at river).

Onto the hand. Both villains are unknown. I have ~1.5 hours total play with them. Both are kinda tight. And, given how little i've seen them going to war with either me or the other lag, I'm guessing they're rocky. Both strike me as not-great players.

Preflop (10)
Hero has 8s/8c on the button 800+stack
V2 limps UTG, folds to hero who raises to 20. 450
SB folds.
V1 calls from BB. ~500

Flop: (65)
4c7cJh
Checks to hero who bets 40.
V1 Calls V2 Calls

Turn Kd (185)
check, check, check
I'm not folding out the FD, I feel like its assumed I'm going to bet here with another barrel. Given that 2 of them called this time, I'm significantly concerned one of them has the J.

River 3h (185)
V1 Checks
V2 bets 75
Hero?
(also, V1 is making it obvious that he is done with the hand)

I know it sounds like a 'meh' spot; but I'm really out of sorts against unknown tightish players here. Flush draw missed, and i've got to be expected to be the kindof guy to call light, I don't think these guys are great, but they are not low-stakes droolers.

It's close but I'd call and expect to be good <40%. I think you have to call lighter in this spot than I normally would because of V1's obvious disinterest on the river, which I think V2 will respond to by bluffing more often but not Vbetting much thinner.

FWIW, The obvious disinterest was only apparent to me after the river bet.

Do people see tightish unknowns value-bluff the missed fd?

Played fine, I would fold river, v2 likely has KTcc or some such hand

I don't think that's a bluff

56 got there on the river. I have never seen rocks bluff in a pot with 3 or more players. This looks like a straight or a K that was on a flush draw.

I would fold now for sure, but I would have barreled the turn as well to potentially avoid this problem. If they are both "tightish" as you say, you might have gotten the one holding a Jack to fold. Your hand now is only a bluff catcher.

almost best turn to bluff ever, i'd prob bomb this turn. as played, fold.

Results. I played the turn as played because it was VERY rare that i encountered resistance from these players. I figured there had to be a better spot (e.g. after a river 2 outer for all my winnings, 1 hour later I was up 300 again with raise preflop + cbet + stop when hitting resistance against those 2 tighties, or double barrel against the one dude who folded to it.)

I folded river; so never saw his cards. I later asked what he had, the response was: 'was that the flop with the 7 on it?" me, "yeah." V: "I had a set of 7s"

If he had said a lesser hand I might be more inclined to believe him, but maybe he was telling the truth; it would fit my villain model of him. Thanks for all the responses, I wanted to see if this was a standard fold (it seems that way, with a couple comments of bomb turn, which is a line I like against different villains)

Open bigger, bomb turn.