If you want to go to the new one use this, then click the pic.
https:// 8ch.net/greatawakening/catalog.html
(remove the 2 spaces that break it)
I don't know how or where to dig but I know what you should look for. (Remember that some of the shooters had military background and got mental health "treatment" through military ordered or refered.)
How did they get into mental health system? Family court, child services, Community Resources available, school referals/ordered, Police involvement?
Then what Mental Health Group/Agency/Clinic did the therapy for that referral agency at that time.
Then list of employed/subcontracted at that time. Then dig background of that list. Political connections, education, prior work experiences. Who the bad guys are should stand out and maybe patterns will emerge.