A few months ago I reported an issue with from_dataset not working which was unresolved:
After studying some of @rich.bateman 's examples I noticed that all of them used a csv file as the referenced dataset. The referenced dataset I had used json. When I changed mine to csv, from_dataset() worked!
This limitation should be mentioned in the docs until it is resolved: Mockaroo - Random Data Generator and API Mocking Tool | JSON / CSV / SQL / Excel