I wonder which songs they will have to choose from Neil Diamond week. He has a ton of songs and some of them are kind of strange. (his early years - like Porcupine Pie)
With the Beatles they limited them the first time around to the early years.
Unless you've seen some of Weber's musicals, or maybe caught Weber tributes on PBS or something, you're probably right. Also, the vocal abilities of the remaining contestants appear to be limited to modern pop. So a very large amount of Weber's songbook will be out of their vocal reach, which may lead them to do some of his less well-known songs.