Hey,
It is a viable method.
You can sync Wahoo and Garmin with RunGap, and both are multidirectional — meaning they can send and receive workouts from one another (or from other sources).
It is device-based, but you can configure RunGap to be automatic. It syncs and shares using some heuristics (battery level, Wi-Fi connection—the documentation doesn’t explain this very clearly).
Thus, the sync won’t happen if your iPad is switched off.
Wow, quite sophisticated flows you have here.
Did anyone figure how to get Form swims to Garmin Connect so it would account for that training too?
You can export a FIT file from the Form app and upload it manually to the Garmin Connect website, but I’m pretty sure it won’t affect training load, readiness, etc.
Man, kudos to you guys, but holy cow this thread just shows how broken all this stuff is.
I don’t big brain stuff like this, kind of seems excessive to me. 
I use my garmin for everything, I have workouts on TrainerRoad. Send the workouts to garmin, do the workout.
Look at it later if I want to on intervals or training peaks.
if I did more than last week I already know while doing the workout. Do more next week, I know I’m improving, PPP.
Wahoo Bolt → Wahoo app → Strava and TR for outdoor rides
TR → Strava for indoor rides
Wahoo Tickr X → Wahoo app → Strava for any other activity