Interesting Tournament Spot

Tournament over the weekend. Day 1. Folds around to hero (120bb) on the button with A9c. Opened 2.5bb, both blinds call (20bb and 40bb). 8.5bb in the pot with the ante.

8s 9h 3h flop. Checks to hero. Bets 6bb. SB jams for 17.5bb. BB flats it, has about 20bb left behind.

We block 99, have top top. It's really a good flop for our actual hand. Hearts or a combo draw could be either of these actions, 88 or 33 could be in either range, players seemed passive so I did believe they could just flat an 88 vs the button open. I'm between folding and just re-jamming. SB in particular had taken the check jam line a few times over the last few orbits, did not see what it was done with. He claimed it was top pair, but I also saw him claim he folded QQ in one spot, but saw an ace flash when he folded... So of course he was lying Phil. Was ready to snap off the original jam.

Ultimately just decided to pick a different spot and folded. Discussing with a few people and opinions were mixed. Some said you just have to flick it in there, at least a call. I just didn't know what to think about the BB flatting the jam. Feels really strong, like he wants me to come along or rejam.

Thoughts? Will post results later to not affect opinions.