I am guessing that while the service may be available in said global areas, JRiver would be required to pay for separate licenses for each of those areas
I doubt seriously that it is an issue of what JRiver will or will not pay (with the recognition that they aren't bleeding money like Apple).
As others pointed out, international music licensing is (intentionally) incredibly complex. Media companies have interlocking sets of agreements which vary country-by-country. Eg: In country A Sony might have an agreement with streaming service Q that they have exclusive access to their catalog, but only if they comply with stipulations X, Y, and Z (one of which is that Sony must approve any new API licensees). In country B they have a similar agreement with a completely different service, and this one has no API and no third-party clients of any kind. In country G they have no exclusivity, but there's some most-favored nation clause on pricing in their agreements so the fees are flat and fixed at prices only massive services can justify. And, so on and so forth. And then each music company has their own licenses, and oh yeah, there's ASCAP and the performance rights groups too to deal with.
And, many of the services, of course, have no public APIs at all.
Private deals for closed API access with a streaming service are going to be a tough sale, because they're going to see JRiver as competition of a sort. The same reason Twitter doesn't want (and is trying to kill) third-party "traditional" clients. If they let you access their (valuable) content, you have to bring something to the table. That's why they'll allow products that "add to" their service, but not directly compete with their own clients. If you aren't Apple or Facebook and your userbase isn't massive (and locked in), then they don't have to pay attention to you and just give it to you. Their goal isn't collecting five pence from a few developers. Their goal is getting in front of huge numbers of consumers, while retaining their own branding and platform (so they don't become just one more radio station in a sea of free radio).
To even negotiate most of those deals, you'd need an army of high-priced lawyers to travel to Bermuda and meet with people and...
No, they need streaming services with public APIs, if they're going to be big and international, I'd guess. Could get lucky I suppose, but even if so, I'd be cautious that it might not last. Even the ones with public APIs are pretty likely to close up tight if/when they get huge, and close up shop if they don't when the VC money stops coming in.
So... That's a frightening prospect.