The main map of the area in Episode 2 ("The Sea of Moving Ice") contains effectively 2 floors: a series of hallways and rooms on the top floor, and a large cavern as the bottom floor.
The dragon, Arauthator, is located on the bottom floor. Many times throughout the descriptions for rooms on the top floor, there are statements about kobolds raising an alarm. Can Arauthator fit in the hallways on the top floor?
The main hallways are about 15 feet wide.
I'm not sure what kind of dangers the PCs really suffer if an alarm is raised unless Arauthator can come and attack them. I'm not sure if there is room, but I also don't think it makes a lot of sense to have a Trophy Room and such if Arauthator can't come up and see it.
Can the dragon fit?