I fail to see the problem here. TS19 and TSW are developed independently from each other, which includes the routes as well. So TS19 getting a route does say absolutely nothing about TSW. Also it would be nice if everyone on this forum could at least write 2 or 3 sentences in a post instead of less than 10 words.
I doubt that. Most likely the UK route is nearer ready for release than any US route, and they already had very similar stock already out there for it. Not sure they can do that with any route
The US getting a route on TS19, would give me encouragement. I wouldnt expect all the research thats gone into creating such a DLC to not also benefit TSW.