That did the trick; thanks Dead Guy! I'm not sure which ending is going to go down, considering that I informed the Wrights about the Sierra Army Depot, but also considering that Bishop should facilitate the NCR expansion to New Reno, so I'll have to wait and see!
So it looks like I've backed myself into quite a pickle unintentionally; I desire to kill Westin for John Bishop in New Reno, and thus aim for the NCR absorbs New Reno ending (and avoid the Vault City Lynette & Westin marriage/independent ending), but it looks like I inadvertently messed that...