On a very draw-heavy J-high flop in a 3-way pot, top pair with a backdoor flush draw should mostly check; once HJ 3-bets and BU cold-calls, folding to the shove is the right, disciplined decision.
Three-way on Jc7c9h, we’re on a very connected, draw-heavy board with SPR ~3.4 and only a slight range advantage. Solver prefers checking a lot here and using small bets when we do bet; with top pair and a backdoor flush draw, checking is preferred, but a small c-bet is acceptable. The 4.4BB sizing is a bit on the big side for this multiway texture.
Note: C-bet sizing is slightly too large on a very draw-heavy multiway flop; checking or using a small bet is preferred.
After we c-bet, HJ 3-bets to ~89BB and BU cold-calls, so the pot is now ~150BB and we’re facing a shove of ~21.4BB to win ~150.6BB, needing about 26.6% equity. Multiway, HJ’s 3-bet range is tighter and BU’s cold-call is very strong, so our equity drops and we’re often up against sets, two pair, and strong draws. Solver data is for heads-up, but even heads-up it prefers calling with top pair here; multiway, folding is the disciplined choice.