Using one of his tools from his duffle bag, he chips a decent sized sample from the wall and seals it into a ziplock bag. A sharpie is used the label it, then he takes another photo with his phone where he chipped out the sample to show Sadie.

With no more room to move, Benjiro reverses course. As he goes, he takes occasional photos and samples from the tunnel wall approximately every quarter mile. He snaps a couple different angles when he meets back up with the body of the mouse, then turns away from the tail to follow the cavern around to try to locate a rear paw.