He is not.
I have conducted some further research. This seems to be related to a problem with Sovereign Glut. My friend used Glut's animate dead ability on Gekh Coal after we killed Gekh as part of Glut's quest. This trigger combat with the animated Glut so we just killed him again and move on. Apparently this has permanently broken my friend's character, and he can no longer summon anything without pulling to party into combat.
I still have not found a fix for this problem, unfortunately.
