Krile though is invested in the Eureka story, so while I imagine the Ivalice raids would become required, I don't know if they'd feel obligated to do that for Bozja. Sure it's a little odd if you go back and do Bozja that the game tries to give you a "she's gonna die" fake out when you know she's perfectly fine in level 100+ MSQ stuff, but that kinda happens to a lesser degree with Krile. Not saying I find it likely she'll join the main characters, just that I don't think Bozja would be seen as required if they ever did. Mikoto would likely just not bring it up in the MSQ.