Ok, I think I got it figured out! So I had only the home dongle (with full Cubase 8.5 license) plugged in and started up Cubase.
VST Transit was not showing. After reading some other forum posts, I read that VST Transit appears in the plug-in information window under program plug-ins.
I opened up the Plug-in information window under Devices > Plug-in Information, and selected the Program Plug-ins tab. VST Transit did not have a check mark next to it in the Active column. I checked it, and now VST Transit is appearing in the VST Cloud drop down!
I remember when I had tried to click this checkmark with the trial dongle plugged in that I received an error message saying that “The Component failed to initialize”. Perhaps this is why when trying to access VST Transit with the full license dongle, I was unable to do so.
I’m guessing that the VST Transit plug-in is ACTIVE by default, and that running the trial unchecked this feature, and must have saved it as NOT ACTIVE in the settings file.
Hopefully this can help anyone that runs into this issue. Just remember, if you ran the 8.5 trial previously, make sure VST Transit is set to ACTIVE in Plug-in Information when you try to access it in the full version.