That worked for my lab instance of VVB 12.5(1) thanks.

Turns out the issue was that the CUCM PUB/SUB were setup with IP addresses. I followed the steps to set them up as FQDN: https://www.cisco.com/c/en/us/support/docs/unified-communications/unified-communications-manager-callmanager/211393-Change-CUCM-S...

I also have the same problem with setting this up. I have imported the self signed certificates into my Windows 10 Client in both Enterprise Trust and Trusted Root Certification Authorities. Jabba works with no certificate prompt.

In 10.5 it was not supported and it did not work without some work abounds, in 11.0 and above I believe it is not supported but it does work.