I didn't think to take a picture of the actual cut wire until after I ran the new line. This is before I stapled the wire to the stud:
I could have sworn I had plenty of distance from the blade to the wire, but apparently the blade must fly around while in action. I still really like my sawzall though, despite the rework I had to do. I decided the easiest and most unnoticable fix was to just add a j-box to connect a new wire to the existing old, rather than rewire the entire line. I had also found a splice in the existing line which was removed with the new wiring fix. The j-box is placed on the office side also. This way it can't be seen when you walk right into the house.
I took my time patching by doing one step each day.
The acoustical texture (aka popcorn) spray was pretty wild. There's a very good reason why they tell you to cover EVERYTHING in the room when you use it. Remember the part in the "Exorcist" when Regan suddenly vomited all over the visiting priest? That came to mind upon triggering the texture spray.
And the final result, or at least final for now. I still need to paint the entire ceiling in the office. But later.