Could you go to https://connect.garmin.com/modern/report/-1/all/last_four_weeks, click on the link "Activity List", and verify whether the Tacx activity is really not there? My Tacx activities are listed there without any issues. Also double-check that you use the very same account for the Tacx Training app and for Garmin Connect.
Also my HRV status looks v different to yours.
If I go to my training load you can see the activities listed in the my activities posted earlier simply aren’t there
ik heb hetzelfde probleem met tacx en Garmin connect. virtuele ritten worden volledig weergegeven in activiteiten, met hartslag, power, snelheid enz.
Bij trainingsstatus worden deze activiteiten niet meegenomen