The companion app indicates a friend is riding. Is it possible to observe the ride in the main app?
Here’s one way to be able to observe a specific friend from the Main App. If you start the main app and then skip the pairing screen (don’t select ‘Just Watch’, select ‘Skip’), you’ll get to your Home screen. From there, you’ll see a little box below with any friends who are riding who you can ride with. (It might not be all of them–if they’re in an event or race, Ride With may not work.)
Select the one you want to ride with. You’ll be taken to them, and your avatar will be there, zooming along next to them. Click on their name on the rider list, and you’ll go into Watch Mode or whatever they call it. Their avatar will be centered on your screen. Once your pedal assist time ends, your own avatar will just get dropped (because you skipped pairing, and heck, you might not even be near your trainer), and you can keep on observing them.