Seems it's back to uncontrollable minions again unless I can find the part of the summoning script that makes the created creatures a part of the party. (if it's not hardcoded again)
I suppose it's hardcoded, too.
You can add the spawned creatures to your party via story script (maybe throw character events on them in the char script and catch them in Osiris) and remove them when combat ends. I hope that doesn't cause conflicts with party size or something else.