I've been working on having both Centova Cast and Plesk running on the same server which challenged me to the point that I gave up but I did want to document what I was working with and if you know of a solution or see something that may help you accomplish dual control panels.

3 matching co-located servers, 5 IPs, WHMCS, Ubuntu 18.04, Plesk Obsidian and Centova Cast
I was able to get both control panels working but plesk force the wrong IP and I was unable to get it to change. Dig the URL replied with the correct IP for Centova Cast control. I could add a stream but could not get the stream to start and icecast is active.
hostname added the second IP and name
DNS A records are set for server hostname and centova cast url for control panel
The Centova Cast server has 3 IPs

I think my failure is not being able to change the IP address that Plesk would allow
I worked with both Plesk control panel and SSH root log-in and I'm sure I missed something simple but came to the realization of why am I trying to run two control panels I just need to set up a custom config for Centova Cast.

I want to make a special thank you to Alexiu for all the assistance the past couple of weeks and in a few weeks I will have 86 genres of 100% Unsigned and Indie Music. Thanks to all who've posted here I know I'm among a few sharp server admins.