I wanted to avoid using anything Google related, however, recently none of my immediate family members were getting any texts from me, or they would get my initial text (sms) but I would not get responses. After about two weeks, I am not sure but assuming it has to do with my family using iphones and all messages going through RCS to me (which on thier end would fail). I used the Graphene OS apps to install Google Play services, I did not sign into my Google account and even my G profile (from my computer) does not have my phone number. I have had 2 weeks now of using Google messages with RCS, not signed into Google and Google store is enabled but no permissions are set. Google Play services only has Network permission, everything else is denied. I would really love to NOT use Google Messages just to get RCS working, but for now this works. Also, just to confirm, when I got to my work computer and check my Google devices (my company I work for uses their services) and check My Devices, it only shows my home computer (Linux based) and no other devices. So to summarize, I have done:
Installed Google Play / Play services through Apps
Did not sign into Google account
Google Play store - all permissions denied
Google Play Services - Network is the only permission enabled.
Hopefully this helps someone. I DO NOT have Carrier Services installed and I am on Tmobile USA.