Just in case, since I didn't see this anywhere, just like ol Kang used to, Multiman ends the puzzle rounds without needing to meet the noted criteria. So if you don't have the strongest roster, maybe this helps. Or maybe I somehow accidentally met the criteria every time exactly as MM flooded the board. Don't tell the dev team.
Didn't find this round of the gauntlet particularly challenging, but it might be fun to run the MM cheese a few times.