This would be a cool origin story for astrophage (from Project Hail Mary, a fun & light sci fi read by the Martian guy)
The reason so many were infected on Eros was because humans deliberately infected everyone on the station. Likewise with the human/protomolecule hybrids.
Like GP said, I think the trick to this book is in the relationship between the 2 main characters, so hopefully they nail that. Judging by the trailer they made it all quite humorous.
In fact, it's so good that it sets a really good example of what an enjoyable experience listening to an audiobook can be.