Correct, the pylons is both out of bounds and beyond the endzone.
We played Florida one year where they were about to score. They fumble and the ball bounces at the 1, hits the pylon, and goes out of bounds. Because the pylon is both out of bounds and beyond the enddzone boundary, it was ruled a touchback.
Same thing with Cam's INT. He catches the ball in the endzone, then touches the pylon. That's a touchback. Damn better than having the ball 1st and 10 on the 1 inch line.