When he saw what appeared to be his own body moving around, Dipper at first assumed that it was just Bill. But then... he thought he caught something odd. It was probably just his imagination, but he couldn't let this go. He had to know for sure. So he followed the other a little ways until he could clearly see the emblem on his hat.
It was not the same blue pine tree that his own bore. As Dipper had suspected, it was a number. The number two.
He gasped at his find. He hadn't expected to be right about this. It was impossible! "No... way. Tyrone?!" He was far too deep in disbelief at the moment to remember that the double probably couldn't hear him. How could that be?! It didn't make sense. Dipper had seen Tyrone's demise firsthand. This was weird. This was really weird.