Alright so I've been doing a bunch more research, and a bunch more talking to engineers and well, here's some "new history". The first locomotive on the line was a 1922 Davenport 0-4-OT from the Wayne County Board of Roads Commission. In 1962 it was converted into a 2-4-2 and a tender was added along with a diamond stack and other "wild west" fixtures. Numbered 76, the Davenport operated on the Frisco line (wearing Frisco "coonskin" heralds) until it was retired in the 1980s. (It was the display)
Several German engines, which are 60 centimeter gauge (close enough to operate on two-foot gauge track) are in use at Silver Dollar City. Two 1934 Orenstein & Koppellbuilt 0-4-OTs were purchased from Peter Buescher & Sohn of Mueater, Germany, in 1965. One of these, No.43, has been restored to service as a 2-4-OT and is in use today. A larger 1938 Orenstein & Koppell 2-4-OT, former Kies unit Schotterwerke Nordmark No. 13, is also in use and retains its large European-style cab. The newest engine on the roster is a 1940 2-4-OT built by KolbenDanek for Hans Vatter, AG., which carries the number 76. There is also a 1918 Henschel 0-4-OT in storage. All locomotives are painted red and carry the Frisco herald. Frisco aided the Herchends when they had problems laying track, the line was then re-named "The Frisco Silver Dollar Line"