DTMG bug?

So in DTMG's kit, it states "Whenever Dark Trooper Moff Gideon would be defeated, if he has 4 or more stacks of Insight, he recovers 100% Health, loses all stacks of Insight, and the weakest non-Galactic Legend ally is defeated instead."

But if Dark Trooper is an ally, they're obviously the weakest, with 25% of their base survivability. So owing to this clause, DT should lose 1 stack of Dark Trooper squad and DTMG loses all Insight. Apparently not! What happens is that DT loses a stack at the start of each unit's turn until it's completely dead. Is this an unintended interaction or am I missing something?