Grimm had 0 HP but still looked alive. Very peculiar. The poison and buffs didn’t clear off of him when they did off everyone else, but there was no damage point count from the poison and he could not be healed. Once Grimm was at 0 HP, Jabberwock’s attack hit Miki and Wilbur as it would if Grimm were dead.
Once all the other heroes died, my team was considered defeated, so the game clearly understood Grimm was dead. It’s just a weird visual error.
Same glitch reported here two years ago: 0 Hp hero not showing as dead
I’m on Android and just upgraded to V25.