Trying Arch-based EndeavourOS and MC32 is available on AUR (using EndeavourOS install MC32 version via ... yay jriver-media-center)
Using openSUSE Tumbleweed (highly recommended) and using Alien to convert the deb file to an rpm works well (I did it on a Debian box). The link below covers it.
https://en.opensuse.org/User:Noee#JRiver_MediaCenter_Setup_on_TumbleweedWith that said, I'm using Debian 12 for my JRiver-based music servers.