I think there's some very neat imagery at several points here: Tiamat's Fang, steampunk arm, the sapphire ceiling, an ancient civ that projects its memories. This adventure wants to tell a very specific story in a very specific way. Maybe it's meant to be the level 1 starter adventure for Silent Gods? As a result it feels like there's very little choice for the players and GM. I wonder how it would be different if Sarah goes in solo, the PCs are tasked with going after her, and then modules describes the dungeon's rooms and passages with clues about Sarah's whereabouts and choices about where to go. If, after the jam, you still wanted to fit the 4 A5-page format, it would require some finessing and reducing the read aloud text. Alternatively, just make it longer. Bold statement to make a whole system for the jam!