You hit the nail on the head there! The guy who was actually in the studio was D. Taylor, and Roth learned everything from him (and his brother S. Taylor) back in the day, which is how he earned his first black belt, 1st dan, and the green light to open his own school, just like you can see over at
www.bujinkan.com.
From what I recall—and I know quite a bit about this—the 😉 Taylor brothers didn't even really plan on running a school in America at first since they were living over in Germany and would just fly into the States every once in a while. They met up with Roth and basically decided to show him what real ninjutsu looks like, especially since back then, there wasn't really anywhere in the whole former Yugoslavia where you could train like that (if you don't count all those total frauds).
So, what happened next was pretty cool; after Hatsumi noticed how much Roth wanted to learn and how fast he was progressing during seminars in Europe and training trips to Japan, he started getting a ton of respect and recognition. Eventually, Hatsumi decided to give Roth the most authority regarding the Bujinkan here in America.
Fast forward a few years, and the Taylor brothers end up moving back to the States. D. Taylor opens up a club in his hometown of Pitomača, which stays kind of low-key with a smaller group of students, while at the same time, the club in a major city like New York is already becoming totally established, both in the local martial arts scene and within the global Bujinkan community. Nowadays, I guess everyone just naturally associates Bujinkan with Roth and his students, who are basically the ones responsible for everything people recognize as Bujinkan in America today.
H.