Okay, since we are discussing what we do know, I wanted to throw this out.
RFG had a cell phone with him. He called PEF on it around 11:30 AM. He was definitely west of Rebersburg, because there is no coverage after that; it is a dead zone.
We know that RFG, at some point, between the eastern end (the Lewisburg side) of that dead zone and when he was around Centre Hall, he turned off his phone. Had the phone been on while he was in Lewisburg, LE would have started looking there, because it would have shown that his phone was pinging the towers there.
His phone had voice mail.
Why didn't RFG check his voice mail in the later afternoon? Someone from staff might have needed to talk with him. His daughter might have called. PEF could have called about dinner plans.
Why is he not turning on the phone?