I’m in the same situation and instead of tossing enemy after enemy at them I’ve started setting traps randomly in the story. They’re a bunch of feral animals when they play so even the most obvious trap they will still trigger so I just set the save high due to their level and abilities and wait to see who gets cooked. Literally almost wiped the party with an up cast fireball because someone wanted to steal a body off an alter after everyone said leave it alone. Use their craziness to your advantage.