https://www.youtube.com/watch?v=VWSa5S6Jn9o
Not seeing how he could have slithered away under a dumpster and still not get bit while under there.
Forgetting the fact these dumpsters are usually a few inches off the ground.
I suppose he could have climbed to get to that other to building to the right but Nick blowing his own head off changed things up for him.
I don't even see how we could say that is Nick's body on top of him.
The initial angle of Glen on the ground shows nothing on his chest while the other angle appears to have a hump where they are clawing at but they are awfully close to his neck.