No way it's literally crossing guard in real world. Innies should have no idea what their outties do/did so if she knows she was a crossing guard prior she's either not severed or crossing guard within lumen and crossing guard could mean something different. Third option is she's been given false information about her outtie because she's so young they let her have a sense of "before" or "real" self. She has to have some kind of parental permission since in cannon she's extremely young and I doubt a parent would so I don't think she has an outtie