While on a settlement defense mission for NJ I had ended the fight by Mind controlling a Scylla Thyreos. When the mission ended the Scylla was not captured and had been allowed to retreat with maybe 300 HP to its Citadel (which I attacked immediately after the NJ mission). The Scylla had reduced HP in the Citadel as explained above but still not sure why it was not captured. I had containment facilities, maybe not on that continent? Not sure if that matters as well?
Not sure if this is, as intended but thought I would identify it.