or if you have any suggestions on how to correct this if it is from my end.
Try exporting it From Wahoo (or from Strava), and import manually at https://connect.garmin.com/modern/import-data
Preferably use the FIT file format. If not available, TCX or GPX would work too.
I’ve just done the same SYSTM ride and had exactly the same thing, syncs to Strava but not Garmin. Found this thread with a quick google search. You’re welcome to add me to your ticket with Garmin & wahoo if you like as another user case. I feel like the export import option will work but that’s not quite the point of the issue we have.