In previous Dolly/Bull threads I have posted lots of really good info as well as links to papers which will show you the known distributions of the 2 species in BC as well as regions of distributional overlap and hybridization.
You are unlikely to find S.malma (Dollies) in the Valemont area as they are not known to occur there.
Genetic testing is the only way to really know what you are dealing with. However the distributions of the 2 fish are quite distinct, so by using that info you can be fairly sure of what you are catching.
The 2 trout in post #23 were caught in the fraser less than 50ft feet apart... From what ive read dollies have been caught in the headwaters of the fraser. Totally could be wrong but they didnt look very similar.
Got down in the 12ft... wind was blowing muddy water from the dry end so fishing was not great. I went to a summer hotspot for trolling and found it was still a stump desert. Found over a dozen usable lures and decrepit reel. A friend got the biggest bull of the trip but i managed a few small ones and we caught a couple burbs as well. The biggest bull had more scars than any other fish i've ever seen. It looked like it had went threw a boat prop when it was little. As always any unique fish that are caught and not killed must be named. Say hello to the "veteran".
Had plenty other activities to do so fishing became a 2nd to prospecting due to the water clarity.