Villain appears to be a solid player.

Question 1. I chose, correctly or otherwise to flat KK here on the btn becuase villain's f3bet% was so high @ 94% . How do you feel about this? I don't remember noticing at the time but I see now that his 3bet% is super tight @ 3% overall which is AK,QQ+, but 3bet of 7% from the SB, How should that effect my decision?

Question 2. As played, having decided to take this line, I think it was a mistake to raise on the turn? It's a relatively dry board and we want to continue getting value from his bluffs and AQ?

Question 3. river ?

PokerStars - $0.05 NL - Holdem - 8 players
Hand converted by PokerTracker 4

BB: 103.4 BB (VPIP: 0.00, PFR: 0.00, 3Bet Preflop: 0.00, Hands: 15)
UTG: 86.4 BB (VPIP: 14.29, PFR: 10.71, 3Bet Preflop: 8.33, Hands: 29)
UTG+1: 56.8 BB (VPIP: 12.35, PFR: 4.94, 3Bet Preflop: 0.00, Hands: 83)
MP: 100 BB (VPIP: 3.45, PFR: 0.00, 3Bet Preflop: 0.00, Hands: 29)
MP+1: 207.4 BB (VPIP: 31.03, PFR: 17.24, 3Bet Preflop: 0.00, Hands: 29)
CO: 100 BB (VPIP: 14.93, PFR: 10.45, 3Bet Preflop: 12.00, Hands: 69)
Hero (BTN): 115 BB
SB: 116.2 BB (VPIP: 18.05, PFR: 13.47, 3Bet Preflop: 2.82, Hands: 353)

SB posts SB 0.4 BB, BB posts BB 1 BB

Pre Flop: (pot: 1.4 BB) Hero has K K

fold, fold, fold, fold, fold, Hero raises to 3 BB, SB raises to 8 BB, fold, Hero calls 5 BB

Flop: (17 BB, 2 players) 5 9 Q
SB bets 10.8 BB, Hero calls 10.8 BB

Turn: (38.6 BB, 2 players) 7
SB bets 19 BB, Hero raises to 38 BB, SB calls 19 BB

River: (114.6 BB, 2 players) Q
SB checks, Hero

I think SPR should effect your decision the most. Villains 3bet range is so small, even from the sb. He is almost never 3betting light, so I think a 4bet is definitely in order. A small 4bet because not much more is needed to get a good SPR on the flop.
I would only flat call here if the SPR is going to be <3 on the flop.

I like the turn raise. The bet on the turn was half pot, and you only need 25% equity to call. Your hand in this spot probably has like 70% equity, so I think a turn raise is definitely justifiable. Also, villain appears to have now bet two streets for value, so it is safe to assume that he likes his hand, and that a turn raise will get a lot of calls.

I think I'm happy to check this one down expecting to see 10j, 66, Qx, or full house.

Flat his 3b ip is fine. You´re hu and has position on him. Calling flop is fine, raising turn is fine. OTR I would check behind. Unless you have some read on him, with 2.82 3b you can just assume he doesn´t even have JJ in his range, so he´s not calling with anything that you beat.

Lol, this villain isn’t 3betting any of the hands mentioned above.

It looks like villain has AA. It’s the only hand that reAlly makes sense to check river. I don’t think jamming river is completely awful (obviously we don’t want a call), however I imagine if villain has AA he is snapping any river bet off anyways.. your line on the turn doesn’t really make sense imo. I mean are you really raising a bare Queen here? You rep the exact hand you have a villain still calls. I check back and expect to see Aces most of the time.