The patches were probably from opening up the wall to get around the fire breaks that are supposed to be there. Some contractors do not install them.
When I installed network cables in some of my families home, I ran into this. Fortunately, there was enough room in the attic to use what they call a bell hanger bit. It is about three feet long and the shaft is flexible. The only problem is to not hit a nail, it will jerk the drill out of your hands.
Something I bought to help is a Rigid fiber optic snake camera. The thing uncoiled is about four feet long. I stuff it doen the wall to see if there is a fire break and where the center is. I find the studs in the attic by the nailing. I built and remodeled homes with my older brother, a lot of framing and sheetrock work.
In my home the basement is only partly finished, so I went from the bottom for cable tv, telephone, network cables and feedlines.