Not sure what the status of the “Ubastet sometimes kills summoned troops” but just had it happen to me, so will add some details.
I had Hero as Orbweaver in first position. Uba cast his spell, hero dies, then summons Giant Spider in its place, then third troop (Medea) gets killed by Uba, and then Giant Spider gets killed by Uba.
I’m mostly certain the Medea would’ve survived the shot from damage alone, but not 100% sure. I wasn’t really expecting the bug, so I wasn’t looking at all the details that closely. The deaths definitely happened sequentially though, none of the happened simultaneously, but they all happened within just the one Uba action.
Also, this topic is no longer stickied, and I had a very hard time finding it.