Switch won't pair with both app and pico

I am having difficulty connecting caseta switches (not dimmers) to both the app and a pico. I have four locations with switch/pico pairs (to replace 3-ways). I want each switch to connect to its designated pico and to the app. I am pairing the picos to the switches directly and not connecting the picos to the app. I have successfully set up three of the four locations (although two of them required multiple attempts). The fourth location still won't connect after many attempts.

The switch will connect to the app just fine, but when I try to add the pico, they won't pair. Alternatively, if I disconnect the switch from the app, it will pair with the pico on the first try. If I try to connect to the app after pairing with the pico, the app returns an error and asks if I want to cancel or proceed without the remote. If I proceed without the remote, the switch deletes its connection with the pico. Then it won't reconnect to the pico.

I've made many attempts (each costing 10 minutes or more). I've done full factory resets on both the switch and the pico at least twice with no change. I had a similar issue with one of the other switch/pico pairs, but it resolved after a reset. The problematic switch/pico pair is within easy range of the hub and is closer to the hub than some of the pairs that have successfully connected. I also have at least a dozen dimmers connected to the app that also that to dimmer picos with no issues. This is a large system with over 20 dimmers and switches and around a dozen picos. I do not need or want the picos connected to the app, so pairing through the app is not the solution.

Suggestions? Please don't respond with directions on pairing through the app; that's not what I'm trying to do.

Thanks.

When using the Caseta Wireless system, you will need to pair the Pico remote into the app. Even if you pair the Pico remote to the dimmer/switch first, when you then pair the dimmer/switch into the app, it will automatically pull the Pico remote into the app. The remotes will usually go into it's own room such as "My Home" or they will automatically be hidden in the app. To see hidden devices, you will go into the Lutron app > Settings > Customize app > Show/Hide Devices.