If this a Vigilante Deku AU then he shouldn't join the LOV as that would make him a villain, not a Vigilante. Also, despite what All Might did to him, the other Pros & his classmates still care for Deku so I can't see him betray them. Though I would love to see Stain's reaction to what he learned All Might did to Izuku (as he thought both were true heroes, so he will be shocked/horrified to learn the truth of All Might)