Realistically they've got multiple options for distracting Chroma and Blaze. The reason they're going with Mira is because it's the option that involves the least actual fighting. They've been told at least some of their backstory and are well aware that the two of them very much do not want to be involved in this but don't exactly have a choice in the matter, so they'd like to avoid hurting them if possible.
Aw :(
Well, at least there's that. And who knows, maybe Blaze and Chroma like the change of pace, gives them something to distract themselves with.










