So the swordsman guy wants to fight Blade, correct? He should be able to handle him, although not nearly as well as if he hadn't been starving for a day and a half.
But yeah, if it's done through PMs a collab post isn't actually much faster than powerplay since you're just changing the presentation and location of the posts if it's faster at all, and powerplay can give more flexibility involving other stuff going on in the meantime and breaks it into smaller, less overwhelming looking chunks. Just my two cents though.