The only thing that comes to mind is that it may be connected with N90. When KFRG tower is closed (2300 to 0700), N90 - specifically, the controller for the ROBER sector (125.7) - handles the clearance delivery frequency for KFRG (128.25). Most of the time ROBER simulcasts on 128.25 when the tower is closed so in all likelihood, this remote station is being used for that frequency. I hope that helps.
Ron