Flatting pre is no bad play OOP. AS played Jam pre or fold, you cannot allow to fold any flop, imo given SPR:

I'd fold pre. Likely to be Aces. Our hand is just dominated by aces (duh, right?) and we have 8% better equity with a crap hand like 78QJss than with these pretty Kings.

Whether or not I'd 3-bet pre depends on my read of pfr. With no read, I'd probably 3-bet.

Same opinion

Squeezing your hand is fine preflop against most CO ranges, as you will push a good amount of equity against a CO pfr range and a BU cold calling range (You have 40% 3 ways against a 30% CO PFR and a 25%-6%3B Range for the BU).
If CO is opening tighter calling becomes more attractive (a 30% range has AA about 11.5% of the time whereas a 20% Range has AA about 18% of the time).
You decided to 3Bet and we are now faced with a 4Bet: If we assume CO to have AA all the time we have 2 options:
- Folding pre
- Call Pre and stackoff on the flops where we have enough equity (we'll need 26% OTF).
Pokerjuice/Odds Oracle can do the math for you in those kind of spots. Here you just have 33% equity against a AAxx range and therefore a pretty clear fold against his 4Bet.
Calling the 4Bets nets an EV of about - 9BBs
Only the strongest of Kings will have about breakeven calls (like KKJTds, KKTTds) here, so we are never going to make much $ by calling his 4Bet with KKxx