I agree, a CA most likely won't do anything unless maybe they are told by their customer (your past creditor) that it should be removed. Nice letter though, maybe you should send to original creditor.
I'm starting to do that and I actually think some are going to be helpful and forgiving! Things happen, and they have to at least try and understand that and be a good company and do the "right" thing in my opinion. Worth a try!!
good luck