Got a call last week to go out to a new oil battery field office and terminate the installed cables. They purchased an RTM. The prints shows each outlet to be two cables one for voice and one for data, there is only one cable in the outlets. They asked us to add a second cable. There is insulation between the floor joist and the bottom is double drywalled for fire rating. The outlets upstairs have a 3/4 pipe stub with the one cable in it. The data cables were installed at the factory, so they are between the fllor jiosts. My thoughts were to get one of those long flexable bits and try to drill down, find the hole make it bigger pull the cable up and then fire caulk. Anyone with a different idea? Thanks