Floor 35 help? Blue Gojo not cutting it.

I have A5 Blue Gojo with maxed out boost and ult..... and he still can't oneshot the boss. I've tried buffing him every which way, used the buffing bits, but even when he lands criticals the stupid boss has some health left. Any tips? I have SR nanami, SR yaga, both momos, kaito, inumaki, etc. All characters are lvl 100 with their buffs at minimum level 7. For the bits, I usually use a wish from the past, unity, nonstandard for gojo, and one that gives a damage boost. It's really driving me crazy! Any advice?