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I stumbled across this thread because I too am currently looking for a way to mount an "old" image. And I am writing this comment ONLY to confirm...
Did you notice the following part: "Symlinked the new gcc to /usr bin/gcc: cd /usr/bin mv gcc gcc-8 ln -s /opt/rh/gcc-toolset-12/root/usr/bin/gcc...
Found this article which seem to help: [SOLVED] Parallels Tools Fail to Install in Oracle Linux VM
Same issue here. (Oracle Linux 8.9)