Buddypress Group Calendar Issue

We have removed Buddypress Group Calendar from our WP site twice (once by deleting it through the admin panel and once by reactivating it and removing it through FTP) and the "Events" Tab the plugin created on all of our forums still will not go away. We want this tab removed please. Why doesn't it delete with the plugin?

http://www.fretbuzz.com

site password: test12

link to issue example: http://www.fretbuzz.com/groups/amps-effects/events/