Yeah in general it seems all the monster skills that target other monsters, other than the shaman revive skill specifically, don't work for bound demons
Haven't seen overseers use their whips on other demons or council heal anything or so on.
It seems like they hardcoded a few demons to actually work while bound, specifically the shamans and vile mother spawners, but most demon skills that would do anything interesting don't work, and you can't bind the silly ones like festering tentacles. But you can bind suicide minions, they just do exactly what their ability does, which is dick all