I just completed a route, also while doing a workout:
Logged back in and looked at my achievement badges:
I just wanted to make sure they are working. I’m wondering if in your case the connection to Zwift’s servers was interrupted during your saving process? The companion app is connected through your home wifi, so could that be why it is showing up on your ride report but not on the game badge screen? Someone smarter than me will have to figure that out. 
Does your activity show up on my.zwift.com? Is the tron bike in your garage?