I *have* to lay this down, right? Turn decision

[Hoop Addict]

8 players left at the FT of a $7 rebuy.

I have KK in MP & open raise to 20K (blinds 4K/8K, no ante - my stack is about 160K after putting the 20K in).

Folds to the BB who tends to play pretty loose passive & he makes the call.

Flop is AAQ rainbow.

BB checks it to me. As I say, he's been pretty passive post flop, despite his looseness pre-flop. I check as well (feel free to critique this).

Turn is another Q.

BB leads for 50K (I have him covered & he has about 50K left after this bet).

There's absolutely no way I'm ahead here, is there? Even at a low buy-in tourney. This opponent isn't particularly tricky or anything.

In fact, this is a super-standard fold on thr turn I think? Feel free to chime in your thoughts on the flop play.