Restrict Job Req creation by Business Unit.

Summary:

I am trying to restrict recruiters to only be able to open Reqs for the BU they sit in.

I have tried the Organization Security but its not working, making me believe i am either setting it up incorrectly or our configuration doesn't allow for Org security.

In the attached screenshots, is what Recruiters see when they want to create a req. I want the Business Unit drop down to only show where they reside and no others.

Also, although i have the Org security profile created and have assigned it in the Data Sec, where do I specify which BU each Recruiter can see. Unlike Person Security Profile, I don't see an AOR section when setting up the Org Security.