Hi Troy -
On macOS, Zwift writes each ride file to this location inside your home folder:
Documents -> Zwift -> Activities
When you look inside that folder, you’ll see a bunch of files with names like “2019-12-27-13-36-20.fit” - when you ride, Zwift writes to the active ride file every so often, so if you made it to the point of actually trying to save out the ride, chances are pretty good that the most recent .fit file in your Activities folder will have your whole ride in it.
Unfortunately, there’s no way outside of Zwift to upload that ride to your Zwift dashboard online - however, you CAN upload that .fit file to Strava, so you’ll have a record there at least.
Hope that info helps you out.