nick142 For me it worked w/o issues (TOTP and Duo Push). I installed it in a separate user profile using the apk download from their website. Duo has an built-in update check, so you get notified about new versions and can then download them (it's not a self updating apk like signal).
It works w/o play service. Note that duo push is less convenient then. You need to close and re-open it to reliable fetch the push.
For me all checks passed, not however that this can variate depending on the policy your administrators set (I had a rather strict one I guess). It could also start to want Play Integrity at some time.