alt Hacker NewsSame here. I've been scraping the data from my Garmin watch for years with very little problems (first with https://github.com/tcgoetz/GarminDB, then https://github.com/sealbro/dotnet.garmin.connect).
The only annoyance is that Garmin requires 2FA if you enable the ECG feature on your smart watch/fitness tracker, but I have a small program that reads the 2FA codes from my Gmail inbox and supplies them to the scraper without too much trouble.
Have you looked at the feasibility of making your own CIQ app to push data from the watch to your alternate internet endpoint?
I have the impression there are permissions and APIs to access sensor history and activity records, but I haven't had a need to dig in and learn what restrictions there might be...