update: This has now been resolved and x2goserver now works with RHEL and is derivatives
The latest update to x2goserver (18.104.22.168-4.1) for RHEL and its derivatives currently have an issue where if you try to install x2goserver it requires a dependency that is not part of Red Hat. xorg-x11-fonts-core is a part of OpenSuse and not Red Hat yet the rpm requests it.
I have asked the question on server fault but it looks like this is a software bug that I cannot resolve without it being fixed by the development team. I have left a message on there IRC. Hopefully someone will pick it up and resolve the issue soon.
The developers have seen the issue and looks like they may of resolved it. Hopfully the fix will go in to the repository soon