I tend to think that, despite the spelling difference, Arkley is probably right that it is Marshal Davis, of Powell:
http://www.hudl.com/athlete/517682/marshal-davis

I had to smile at the first play, where Davis rumbles for a TD (note - defensive linemen never "run" for a TD, they "rumble").

As I watched him land on a QB or two, I was reminded of an old story concerning now-deceased Congressman Jack Kemp, a former NFL QB. In his office there were supposedly two pictures of him as a QB. One showed him covered with mud, in the rain, sitting on the bench, with his face in his hands. The other showed him being laid out by a 350lb defensive linemen. When asked why he had these two particular pictures, Kemp answered, "I have these two because they remind me of two important lessons I carry with me from my football days. The first picture reminds me that you can't win them all. The second one reminds me that the bigger they are, the harder they fall ... on you."

With the additions of walkons to the scholarship players, they are definitely starting to build some depth at the DT spot.

Scholarship players:
Purdum 6'3" 270 Redshirt Senior
Sayles 6'3" 268 Junior
Tautuiaki 6'2" 304 Redshirt Senior
Aloese 6'0" 297 Redshirt Sophomore
Porter 6'1 289 Redshirt Sophomore
Kuhar 6'5" 270 Redshirt Freshman
Arp 6'3" 256 Freshman
McKnight 6'3 267 Freshman

Walkons
Stephens 6'2" 245 Redshirt Freshman
J. Williams 6'0" 245 Redshirt Freshman
Payne 6'1 261 Redshirt Freshman
Chuckwu 6'2" 230 Freshman
Davis 6'1" 270 Freshman (if this is the correct Davis)

* Note: Do NOT believe the above weights. They are either from 2 1/2 years ago, or from when the player first reported, if they reported after 2013. Most of the above players probably weight 10-25 pounds more than is reported above.