How do you get the data from the CT10 collected by the S20 into the Garmin Golf app?

I am sorry. I just came across your post. If your Approach CT10 sensors are showing connected on your watch and you use the clubs they are attached to, when you save and sync your golf scorecard, the data from your CT10s will show on your scorecard both on Garmin Connect web and in the Golf APP under scorecards.

If you have any issues with your CT10 sensors, please ensure you have fully updated their software - from the CT10 manual Updating the Software. More details in the Support Center - Installing the Latest Software to Your Approach CT10.

On the bottom of the Support Center article is your region's Garmin Golf Product Support contact information in case you continue to have issue. We will be happy to assist further.