It looks impossible because of Felix’s low HP, even with his Ralph disk equipped, but Wave 1 is very impossible because Clawhauser and Baloo seem to deal A LOT of damage, even though Baloo’s only damaging move is his basic attack.
My Felix and Anna seem to die first (Olaf too but he can revive), then Olaf (he immediately dies after reviving) and Elsa (they gave her a buff but she still leaves more to be desire) and Gonzo dies last, meaning he lives the longest.