While RHEL and Fedora are siblings we can't mix em' like that. At least I haven't ever seen a server with Fedora pre-installed, or anyone offering support on a Fedora server...
We have a piece of fancy and expensive radio equipment in the office, the control part is a Fedora server, with precompiled binaries that run that piece of hardware. Every system library has frozen version, if you upgrade the OS the whole system stops working, and you just reinstall the disk image from the archive, and by reinstall I mean use dd to overwrite the hard drive partition from a supplied DVD.
Huh, at least it's Linux I guess? I've seen plenty Windows XP hanging around controlling expensive medical equipment and one time even a system were the control part was Windows 3.1. Air gapped not for security but because the server didn't have a NIC.