I actually tried to get Grindr to work a few days ago after reading this thread, but it didn't work for me. Didn't say anything because I had nothing valuable to add. Still don't, just lots of failure.
I tried on a fresh new profile. Installed all of GMS apps. Installed via Google Play. Logged in to Google Play. Also cannot log in or create an account on Grindr.
Granted literally every single permission to both Google Play Services and Grindr. Didn't work.
Enabled exploit protection compatibility mode. Didn't work.
Tried logging in using Google for single sign on. Grindr shows up in the connected apps, but still doesn't get past that point. Tried creating a user using email + password. Also didn't work.
Didn't try phone number or Facebook login because I'm not sure how I'd explain anything popping up to unwat's better half.
Checked logcat. Nothing helpful there.