OK, here’s how to debug this:
1. Enable WordPress debugging and add something like error_log( __FUNCTION__ ); in the function where you add your data to the filter. It could be that for some reason you have not hooked the code correctly and it is not running.
2. When you say that you do not see it in the menu, are you referring to the frontend menu? The frontend menu only lists adapters that are connected. If you have set up the adapter description correctly but have not set the connection settings then it would appear in your admin screens under Wallets -> Adapters and there would be an error message next to the adapter. This will guide you as to why the adapter is not connecting.
Do let me know what you find and if you get stuck.
kind regards