That's part of the original score; I don't know the cue title. It's not on any of the CDs, unfortunately.
The four volumes that got officially, commercially released cover these episodes:
"Vienna, November 1908"
"British East Africa, September 1909"
"Peking, March 1910"
"Princeton, February 1916"
"Ireland, April 1916"
"London, May 1916"
"Verdun, September 1916"
"Paris, October 1916"
"Young Indiana Jones and the Phantom Train of Doom"
"German East Africa, December 1916"
"The Congo, January 1917"
"Barcelona, May 1917"
"Northern Italy, June 1918"
"Young Indiana Jones and the Mystery of the Blues"
"Young Indiana Jones and the Scandal of 1920"
Additionally, composer Curt Sobel released a promo disc of his complete score for "Transylvania, January 1918," and the LEGO Indiana Jones game uses some unreleased music from the show (there's a thread about that somewhere around here).