Lae'zel has a very strong group mentality, so I can understand why she wouldn't be very understanding of someone not choosing to help their allies. I am overall very pleased with her during the epilogue. She also talks about how her son (the egg from the creche) will be able to choose whatever future he wants to have for himself, that does not sound very domineering to me, neither does her plan to return to Faerűn to be with her friends once more after Vlaakith is disposed of.
But that's probably all leading away from the point of this threat. Just in general I prefer an option for the githyanki to decide their own fate without a mythical figure they blindly follow - no matter if that mythical figure is a nice guy or not.
