I will personally refuse to use the return address of MY Kingdom hall. I'm a most notorious case of apostasy locally and a prime suspect. So I will use a random address of a Kingdom Hall as a return address. If nothing else, it will stirr confusion at Bethel.
Use the return address of a prominent Elder in your Cong or in your Circuit.
OR, use the address for Wrigley Field. It worked for the Blues Brothers.
https://www.youtube.com/watch?v=HsHjW8rBRk0
Doc