if the banker had told you that they were going to fill out an SAR and a CTR that would be illegal.
For your friend to say, lets make the deal at a bank so they can do whatever they need to is not illegal. It is illegal for the agent to inform a customer that they(agent) will be filing reports.
I work in a grocery store, so we can't handle transactions of $10k or more. If a customer wanted to spend over $10k with us in cash, and we said, lets do this at our bank so they can handle the paperwork that would be fine.
Now, If someone send money through our MoneyGram service for $3000 and I tell him that I will be filing an SAR then that is illegal.