[Mashiro]

You asked me to look at the issue. Well, here is my though of it (I have never used VNC on any of my servers. Merely just created a guide out of a thread where a VNC issue needed to be solved). It looks like your desktop environment and window manager seems to be broken. All the errors in your log hint that it fails to create a session in the desktop environment due to several things actually missing from the system. Fonts aside there are a lot of critical error messages.

Maybe reinstalling the DE and WM will help? I have no idea. I don't have any experience with VNC.