Here is my hot take. N.B. that I have no idea what I'm talking about. Some other kids tried to use a Microsoft mail service of some kind to access the emails

Here is my hot take. N.B. that I have no idea what I'm talking about. Some other kids tried to use a Microsoft mail service of some kind to access the emails in those accounts (for example, to get a password reset email for the Minecraft account). The login attempts came from Microsoft servers rather than the kids' home internet connections, because that is how it works when you ask a web app to go fetch mail from another account for you. And conveniently, it obscures the home IP addresses of whoever was doing it. Like I said, I have no idea what I'm talking about. Good luck!