BEagle
The NATS NOTAM system works by applying filters to the raw data. In the case of a NRB it filters based on the route you input.
The database of waypoints is maintained from the AIP's of all of the ICAO contracting states. The process for notifying new waypoints and deleting obsolete ones is set out by ICAO and quality assured to ICAO Standards.
If you introduce non-compliant data into the database you compromise data integrity. If it's not an officially notified reporting point then it's a matter of fact that there will not be any notification if it were withdrawn. Neither, in the case of SWB will there be any notification of inaccuracy or unserviceablity.
The routing in the NRB follows the same conventions as the routing in a Flight Plan. If you file a FPL stating that you were routing via SWB you'd get the same problem The only SWB that ICAO recognises is the Sawmill VOR/DME which is near David G Joyce Airport at Winnfield Louisiana.
There was a case some years ago of a fatal CFIT in Wales where the COM was found tuned to the Lands End VOR, which had been NOTAMMED as out of service, leading to the suggestion that the pilot might have been unwittingly following a wandering needle into the mountains. At least in that case if he had read the NOTAM he would have been aware. If it ain't in the AIP you get no notification.