My contractor was to do a knock down finish in all the interior rooms, however, his sub sprayed one bedroom but forgot to trowel it out ("knock it down"). So the wall looks like lots of blobs. To be honest, I didn't notice it at first, only after the painters painted the room.

Is there anything that can be done now, short of sanding it all off and starting over? I really don't want to go that route due to the messiness (getting ready to carpet). Would asking for a discount be acceptable? The room is approximately 15% of the total job.