The article buries the lede by waiting until the very end to talk about solutions like having the LLM write DSL code. Presumably if you feed an LLM your orders table and a question about it, you'll get an answer that you can't trust. But if you ask it to write some SQL or similar thing based on your database to get the answer and run it, you can have more confidence.
Until it mishandles a NULL somewhere in a condition on does JOIN instead of a LEFT JOIN and outputs something plausibly-looking that is just plain wrong. To verify it you'll need to do the work that it would take to write it anyway.