The bank reports your bank transactions to the tax authority, who compare them with your tax returns. If there are significant discrepancies you'll probably get asked questions about your customers.
I know though that this is the case in more government-happy states like Denmark, where the banks send this data more liberally.
Anyway even if all the data would go automatically to the tax authority, that doesn't reveal anything. The company would be paying tax properly on all of this, that's the whole idea of laundering. To get the money into the legal system.
If you can pay $100k in cash for a gold bar, it only takes 20 transactions to launder $2 mill. That's not all that suspicious.
With this new limit, you've now turned that into 200 transactions needed. Now the business stands out more because they tend to use business averages/data to spot things.