Github might have pruning, but you can't rely on it, since their Git management system is quite custom. That said, if the request for the Events (as shown in t

Github might have pruning, but you can't rely on it, since their Git management system is quite custom. That said, if the request for the Events (as shown in the previous link) doesn't show the problematic commit - or a commit that extends it -, I don't think anyone could fetch it without previously knowing the ID, and if they do, it's probably because they already have a local copy.