It occurs to me that since BZ isn't attached to Kaguya, he won't be sealed even if she is.
Its possible that Kaguya may have the plan in motion to the point that she isn't needed anymore to get it to work and BZ will take it from here, until he can release her from the seal later.
That would explain why Kishi has had BZ talking non stop and advising Kaguya throughout the fight if he is actually the FV, like the Emperor who doesn't fight himself but has other people do the fighting for him.
Its possible that Kaguya may have the plan in motion to the point that she isn't needed anymore to get it to work and BZ will take it from here, until he can release her from the seal later.
That would explain why Kishi has had BZ talking non stop and advising Kaguya throughout the fight if he is actually the FV, like the Emperor who doesn't fight himself but has other people do the fighting for him.