It's been a month with no response from ZenLabs. I'll take that as a "no" that it's not possible to view the current status on a Garmin watch while running.
Seems like both a shame and an opportunity...
Is it possible for the Android C25K Pro app to work directly with a Garmin Forerunner watch (model 235 in my case)? I'd love to see walk/run time left on the watch face rather than having to pull my phone out of my pocket and unlock it.
The C25K Pro app is running on a Pixel 2 XL / Android 10. The Garmin Forerunner is paired to the phone via BlueTooth so everything's connected.