Really pleased you’ve got it sorted! I know frustrating something like that can be.
ps Bogus Agents tend not to go in much for fixing stuff 
That link I posted was to the official Microsoft Support site (as you can see from the address) so there will be no issue.
Whilst right to be suspicious of support agents taking control of your computer, it is a far easier and time efficient way of doing things IMHO. As long as you’re contacting them through official means, and it’s not some unsolicited random contact from their side claiming you have a problem with Windows, then you’ll be fine.