I hate the place with passion, and I have no idea if the "spoilers" are true, but we can speculate. Here we go:
LE and HL are the only one who will sing in this episode, its one act. The other scenes with RSL (alone in his appartment) and House`s Team (Zombies) and Cuddys sister are hallucinations.
Other news are that episode 19 will be another highly Cuddy centered episode. It is called Last Temptation and it will show the evening before the House/Cuddy marriage. You heard it right!!!
Thanks @Norea83 for finding this!!
.........Also, based on what was rumored about the original level of Huddy (several episodes of just House & Cuddy on the road & next to no PPTH), this current level of Huddy may be regarded by Shore as a step down. Who knows?
So the road trip deleted in the middle of the season was Huddy????