Hello! Yep, Charles can come back with his memories, either recalled in bulk or gradually returning to him, whatever you prefer! You can also completely wipe out his game memories, if that's easier.

If you're reapping, unless you're picking him up from a different timeline point that he was originally brought in with, you're fine to comment to the applications page with a link to your former app, and just signal you're repicking — no need for further fuss!