The guy in the diner with the shovel is silas, he also has that black dress beside him.
And when you leave to the RV after eating in diner, the RV door is open, and bathroom door is jammed, meaning Silas hides inside the RV. Later the guy walking outside behind billy through the window is also Silas. And the guy whistling near the river is also him, trying to get you there so they can kill you and sacrifice you.
Also, i think conner is also involved as he is always trying to send you in the woods.