Time for a visit to Six Bells Jn, back shortly.
I have done some more research. If it is this particular tour it only went on the 4th rail network in two places. Gospel Oak to Wembley Central, however the exact route is not show so do not know if it went via Camden Road or Willesden Jn LL. It may not have gone on the 4th rail network at this point.
Later the tour went Euston - Willesden Jn LL before derailing at Kensal Green Jn and being cancelled this has to be on the 4th rail system. This leaves only a very limited number of stations (Queens Park - Willesden Jn LL which include 4th rail). The only island platforms are Queens Road and Willesden Jn (this includes the section up to Wembley Central if it went on the DC earlier in the tour).
At this point Willesden Jn is looking good but I will cover the other option of Queens Park.
All this working out and it will be another tour!