There have been German browns planted in East lake in central Oregon. I think that my son's 30 incher was German, but it didn't smell of beer! so I can't be sure.
A lot of the brown trout I have caught were in a river. The school brown trout were caught alongside rainbows, but solitary browns were much harder to catch and seemed shy of sunlight, so it cut my hours of fishing for them.
There is a section of the Deschutes river that someone caught a 15 lb brown trout. Looking at the habitat, it was perfect for big browns because there are plenty of weed beds for the fish to hide in.
It's fine to catch fish in a school, but it really interested me to fish for individual fish.
Doug