What version of Mac OS are you using? I am not seeing this with Acrobat DC on Mac OS Sierra 10.12.6.
I think at this point I would try wiping out one of the Macs with this issue and then re-installing a clean Mac OS system and a fresh install of Creative Cloud.
Just a thought on the Macs that are doing this. If they have wifi access enabled try turning it off and rebooting and see if the Acrobat memory hogging still occurs.
Is it an idea to uninstall all the Adobe stuff, clean all the remains withe the AdobeCleaningTool and make a Time Machine backup. After that I install a fresh OS from scratch and use the Migrate Assistant to migrate all the apps and settings. When that is finished I install all of the Adobe stuff.
Without reading back through this thread...has anyone with this problem tried creating a new admin account on their Mac and running Acrobat from the new account?