Team just needs to get Alert on everyone.
I think it's just a slight matter of being an underlevelled arcane caster in a scenario where surprise attacks are an option. If the wolves rolled low that fight would've been a cakewalk.
Having a D6 hit die, below average AC, not having a cool super power (Berg's healing, Jubilant's flying), and being out in the open got the caster killed. That's what happens to casters in general. In the boss fight at the end she was untouchable because spell range and maneuverability is OP.
A realistic solution would be the cast just expressly saying that they form up such that the caster is flanked on every which side by the others. That's generally how you keep your OP casters alive in every D&D edition. Delta Formation!