Granted, I'm a radio newb, but it looks to me like you might have discovered a new NSRS site. Perhaps the pros on this forum can confirm this.
A location-based search on Laughlin (50-mile radius) at FCC.GOV returns these active licenses for 856.7375:
WNZB252: North Las Vegas (FB, FB2C), Department of Transportation.
WNZB253: NV, Statewide (MO). Department of Transportation.
WPRY297: Oatman (23 KM SE of Laughlin) (FB2C), NSRS (DOT, etc.).
From what I can tell (and this despite the RRDB's abismal lack of location data) Oatman is not listed for NSRS in the RRDB. The "Laughlin" site shown in RRDB corresponds to "Christmas Tree," some 18 KM NW of Laughlin. And to top it off, there's nothing else listed in RRDB remotely close to Laughlin employing 856.7375.
Dave