The w53 p. 583 and the w55 p. 638 both identify the "false prophet" with the "two-horned lamb" of Rev 13. Rev 19:20 is the verse that ties the two-horned lamb to the false prophet. So this viewpoint goes back almost 70 years for the WT.
I got those two references off of the online WT library, by the way.
Babylon the Great is also referred to as "the great harlot" (Rev 17:1) and as "the great city" (Rev 17:18; 18:10, 16, 18, 19, 21)
There is also another "great city" that resembles Jerusalem (Rev 11:8; 16:19)