Sounds like all they did was pass it around the departments, eventually overwriting the drive with the original factory disk image, hoping for the problem to go away... Not what I'd call expert work, but that's semantics. Well, wait - that's how you actually fight with possesed objects
Needless to say, as long as everything is backed up and you stand a fair chance of getting a decent new unit as a replacement, you went to the best place. Based on your description of their approach to the upgrade towards W10, that ending is surely coming soon.