As a comment I would also suggest that though you "authorized" them to pull for 20 days unless you have a properly executed agreement which both sides, meaning both you and the credit grantor signed (more importantly for you the credit grantor) that you are not going to be sucessfull as they could come back and say "by your authorization we pulled your credit report and although you stated a 20 day limit we never agreed to that therefor we followed our rights ect ect...."
I think you will be hard pressed to get this pull removed. Sorry :-(