Fold pre-flop AJ is dominated a lot by his opening range from there. Now you've got that flop I see absolutely no reason why you wouldnt want to get it in, AA and JJ are pretty damn statistically unlikely and you're way ahead of his stacking off range here that'll likely mainly include AKs and AQs. If he has an underpair, he'll likely shut down on the turn anyway so just go ahead and raise up this flop and try to get your money in, it's defo not a spew.

You say raising vs JJ and 99 would be a spew, well yeah if you saw his cards it obv would be, but you need to play vs his range not 2 unlikely tiny parts of it.