One legend that I have heard about the statue on the fountain sounded like an urban legend to me until recently. Since I didn't pay it much mind, some of the details are foggy, but here goes:
Long ago Adolphus Busch used to visit a bronze workshop in Germany. He was particularly interested in a sculpture of a "perfect, nude German woman." Apparently, he liked this sculpture so much that he would visit the shop just to see how they were progressing on the statue. He also made sure to weigh in on how he thought they should improve it.
I don't know if this is true, but after doing some research, there is proof out there that Adolphus Busch and the sculptor, Johannes Böse both knew each other, and the timeframe of when they were living and where they were at the time seems to give more credit to the above story. Adolphus Busch was very rich in the USA, but he was still famous for his love of Germany. He even paid tribute to Germany in the US by founding some of America's first German towns, several of which were direct influences on Rhinefeld at Busch Gardens.
Therefore, Rhinefeld might be better described as a representation of Adolphus Busch's Germany in America, rather than a recreation of any town in Germany itself. For instance, Grant's Farm in St. Louis (whose centerpiece was/is a German Biergarten) was likely the primary inspiration for Rhinefeld. Busch Gardens even used photos of this place in several early promotional materials for The Old Country. You may notice that the iconic stork sculptures on the chimneys (a very German thing, I'm told) look nearly identical.
Another feature of Rhinefeld is the Holzbrücke: the wooden bridge into Rhinefeld, based on several real bridges in Germany. Even more uncanny, is how one of those bridges has a custom river basin (predating concrete) that was made to eliminate sediment and create clear water at all times. This is very much like the basin under Le Scoot.
One way or another, whether based mostly on "real" Germany or several American-German towns, Rhinefeld is loaded with real history that is hard to trace since most of it dates back one hundred, and even several hundreds of years before Busch Gardens Williamsburg ever existed.
One more rumor: I have heard that the figures on the Glockenspiel are antiques that span over three centuries. The oldest ones are probably the husband and wife. The underlying narrative of festivities at a royal wedding (jousters, jesters, royal horses and coopers performing the Schäfflertanz) is nearly broken because of those two since they are the only ones not associated with royalty.