You should avoid asking additional questions on an existing post that already has an accepted solution. If the accepted solution does not resolve your issue that you may be having a different problem.
You would get better visibility and a help if you were to start a new question.
That being said, if you are having a "javax.net.ssl.SSLHandshakeException", you issue is during client authentication and have not even the point of verifying client authorization. So you need to take a closer look at the keystores and truststores you have setup on both your NiFi and NiFi-Registry to make sure that a mutual TLS handshake can be successfully negotiated.
Feel free to ping me if you start a new community question.