site acting buggy on load

the folks i created the site for foolishly did an upgrade without my consent. now their site will not load, wp-admin does not log in and if it does it brings up a blank page. The site however displays no errors.

ive done all the “WSOD” remedies and nothing has worked. ive disabled plugins, themes, took out extra space from the ?> tags… nothing.

i have even downgraded to a previous version however i think the database has been corrupted since nothing will load in an older version either.

im thinking to just start over, new database, new theme and loose all of their info. any suggestions or help please??

site: maclaarte.org/main