You asked a similar question some time ago and we suggested updating apache and checkmk. Didn’t that work?
However, to answer your current question: No, I haven’t tried to uninstall Apache and I doubt anyone has. It’s for a reason that the RPM package of checkmk lists Apache as a dependency. It’s because, well, checkmk depends on it.
But you can ignore all these checks and break the dependency, presumably also break your checkmk installation. If this is what you want to risk, then try
rpm --erase --no-deps apache
Before doing so, I’d try to stop and disable all Apache instances and see if your checkmk installation is stil usable without GUI. To do so, run
su - SITENAME
omd stop
omd config set APACHE_MODE none
omd start
exit
systemctl stop apache2.service
systemctl disable apache2.service
Now no apache instance will be running and it’s quite easy to undo these steps.
Please let us know how your checkmk is now behaving.