we are carpet and upholstery cleaners, whilst I do vac out the crevices as a matter of proffessional pride, I am not going to remove all the debrise frome inside the suite. The equipment that I hae invested in is not designed for that. Unless you are advertising wrongly ie using stupid terms "like new" etc, then the customer has nothing to complain about. The debrise that goes into a suite is not upholstery cleaning.
I would have reacted to the call a little differently to you, in all the years in the business I have not seen anybody advertise that they will remove all the crap that has fallen below the upholstery.
Peter