I think the fact that they used the meat of a dragon to ressurect her accounts for all her strangeness (leaving aside that she was already behaving kinda weird when we saw the memories of when she was at the mage academy/school).
The dark elf is definitely trying to get someone back to live here, the foreshadowing is getting kinda thick here and then there is the last panel where she stares at the remains of the ressurection spell.
My guess would be that the team either has to go rescue the next "princess" (Marcille), or the dark elf will tell them in no uncertain terms that she won't allow them to make it back alive unless they reach the deepest part of the castledungeon.