That might be the issue... FFXIV has serious security flaws and lack of validations. It is highly possible that weak security (actually the lack there of) with respect to 14 is the issue.
Edit: But this would only be the case if every person who has been deleted also has a FFXIV account tied to their SE management/pol account.
I suspect that it is more than likely what Byrth is saying since the issue with FFXIV seems to be isolated in that it can not be used to affect other client users.
