Personally I don't see how reinstalling DirectAdmin is going to help unless you completely start from scratch with a new Operating System...
The install.sh will overwrite the files. There is no uninstall script for DirectAdmin. You will have to remove it and all remnants manually and then start over using setup.sh (if you completely want to wipe everything + data)
I would highly suggest trying to undo what yum did, but that's just me