There isn't really a good or bad answer to Linda's excuse. Relying on a trustworthy prophecy to get the best outcome for everyone isn't a bad thing, but at the same time, choosing to trust a prophecy that claims a child must bear a burden (which is a literal torture) for the sake of others is never not irresponsible. Guess we just have to accept that she made her decision, anyway.
Looks like we're starting to head towards the end of the time travel part... I wonder if the issue has been resolved ? I assume the curse itself is still to be taken care of, but did Elsa taking on the curse was the solution to mitigate its power and prevent the demon attack ?
That they'd have to be separated was obvious, otherwise the timeline would be messed up. I'm not particularly seeing in a good eye the whole "You pretty much sacrificed your life for my family, but now you're a liability, so take this money and leave". Nobles gonna be nobles, and well, that guy already has a bad ending in store for himself, anyway.
TL;DR Adults suck, Evie's job is done, Elsa still unlucky.