When I press CTRL + F12 I get the controls for the Jet Blue hangers and all that, but nothing for GSX services
You you see the scenery, and of course the YouControl menu, it means ALL your running software is installed and running correctly, otherwise you wouldn't have anything, not even the scenery so, just forget everything you read about VC++, antivirus, etc. Everything's working.
If you don't have the GSX menu, the only possible solution is simply you haven't installed GSX. Or, while uninstalling and removing, you mistakenly remove it, for example uninstalling by replying YES to the question "Do you want to remove the Couatl engine?", which obviously alerted you that every other product that use it would stop working so, this clearly includes GSX so, if you did that at any of your steps, you must reinstall GSX.