Krile "feeling out of place" was actually the entire reason she came with us to Tural. She's felt like an odd-one-out her whole life thanks to her flavor of echo and especially lately as the only main Scion with combat capabilities that was otherwise useless in the final battle on Ultima Thule. Then, the mysterious earring and letter, her switching to Pictomancer, and finding out about her family.

Her finding her actual tribe and living family and suddenly not knowing if staying with them is what she wanted was out of the blue so much as it was that critique of base Dawntrail that Krile's development kept being downplayed despite setting up the pieces for this a while ago.