I guess they would force turn mode until the 15 rounds are done (?)
I certainly hope so.
Can't you even force turn mode on yourself if I remember correctly? They showcased that a while ago as a way to navigate traps and safely prepare ambushes. But possible of course that it got removed?
Oh yes you can ... presuming you do that in time.

Do you remember that HUUUUUUUUUUUUGE amount of feedback about companions, or even PCs standing in fire/poison as combat ended and dying instantly, bcs the game was dealing its damage in real time?

I do.