I would have said "So, if I do that, I can pay off my existing amount, and I won't be adding to my debt at all?", "So, I'm actually incurring more debt by transferring the balance?", or something.
But, frankly, if you clearly stated in the report that it was spontaneously mentioned by the banker, I would have thought you were golden.
But a "fee", and clearly stating that you want to pay off outstanding debt seem to be totally separate and different things. After all, it is up to the MSC and their client.
And also, I doubt I would have been "thinking on my feet" fast enough to actually say any of the above things.