How do you know the wall wart is not a fake one?
I noticed that with my mobile wifi (Huawei) which I generally leave plugged in, when my friend plugged in her Windows 10 tablet to the same power outlet (2 sockets), it suddenly noticed it as a new USB device. I don't ever plug anything in there except a charger for my bike light so had never noticed but I don't know if it has an autorun to install drivers they often do. Obviously the data wires are joined there..
How do you know your security guard is not a fake one?
(I'm genuinely surprised that the standard DELL and HP corporate workstation doesn't have its front USB ports deleted and its rear port access covered by a lockable metal cowl.)