Making mate default display for all users at local level

Any tips on hard setting a Centos 7.4 virtual machine to run mate as default DM for any users that log in without modifying users #home/.xsession

Looks like the /etc/sysconfig/desktop setting doesn’t work with mate and neither does update-alternative -set x-seesion-manager. Also tried deleting all the DM's except for mate.desktop in the /usr/share/xsessions and nothing seems to work.

I couldn't find any support forum for centos here so trying this group. Thanks in advance.