BuddyPress.org

could be some leftover DB value that didn’t get deleted that’s throwing things off.
Just to be sure it’s not a bad file, unzip the same v WP installation and overwrite that file with a fresh one.

Although the error lends to a botched plugin (there are no shortage of them, open source….)
you could axe the entire plugin folder and try again.

Just back everything up often.