HWD
The Narrow Route Brief gives you by default a rectangle 10nm either side of your track. It also gives you any NOTAM affecting the ATZ of your departure and destination aerodromes.
If therefore you do what you did you will get no en-route NOTAM as your route is zero length.
As you suggest the answer is to stick in a waypoint or a different detination. However please bear in mind that what you get is a rectangle plus the ATZ's. not a radius round the a/d's.