Are there any known legitimate software programs which create false 3rd Party Modification flags?

This is an actual true "I'm asking for a friend" question for the support/moderation team. I have a friend who has casually played League for a few years, but just this year decided to start playing regularly with his friend group. His first account, shortly after hitting level 30, was banned for 3rd party mods, and he filed the requisite support tickets, but made a new account to play with friends while that one was dealt with. Then, strangely, the new account was banned for the same flag before reaching level 30. And now, a third account was banned for the same reason.

Some notes here: not that it counts for anything, but I can vouch that no modifications were made to his client or game files, and no 3rd party apps which you would expect to interfere with League's client are installed. We're both young professionals in Manhattan who honestly don't have enough time in the day to think about modding a game. I can provide the necessary summoner names/account names in private messages, but this post is for the more general question, if there's any programs that are known to cause what in this case is clearly a false flag.

Also, one last note: the message which he got three times cites the Terms of Use as grounds for the ban. As a recently graduated lawyer, I'd love to know precisely how a ToU violation can be backed up with little more than "we can't tell you precisely what you were banned for because it would disrupt ongoing investigations". His first account was an account in which he spent a good chunk of real money, and was gifted a number of things from people like me, so there was actual user value in that account. It would seem that a user, using an end product in a way a merchant would reasonably expect it to be used, only to have his ability to use the product taken away would violate one of the standard implied warranties (merchantability, fitness for a particular purpose). And while Section XI of the ToU does waive implied warranties, both California (Riot's jurisdiction) and New York (the user's jurisdiction) have pretty clear case law stating that waivers are not upheld unless reasonably bargained for and they are found to be not unduly harsh. Here, a loss of a pretty significant amount of money with a customer support system that seems unwilling to assist its users would seem to be unreasonable, and a shrink wrap waiver of warranty is, by its nature, not bargained for. This is a genuine inquiry into the process at play here; I'd love to get info from legal as an inquisitive new lawyer.

Thanks guys!