The player in question is not completely outside of the tackle box but he is completely outside the frame of the second lineman from the snapper in that diagram.
Here's the rule from this year's PDF:
2. Before a change of team possession the following players of Team A are restricted
with regard to blocking below the waist:
(a) A lineman more than seven yards from the middle lineman of the offensive
formation at the snap.
(b) A back aligned at the snap with the frame of his body completely outside the
tackle box or completely outside the frame of the body of the second lineman from
the snapper in either direction toward a sideline.
(c) A back who is in motion at the snap and during this continuous motion was
outside the area in b (above) any time after the ball was ready for play and before
the snap. Note: A back is not restricted if he starts from a set position inside the specified area and during that continuous motion he does not leave the area (see
par. 4 below).
I guess I should've also said it didn't seem like he was completely out of the frame of the body of the second lineman from the snapper either, although I admit it seems very close and is like splitting hairs.
I'm new here and to the trade and am trying to learn as much as possible. I appreciate all the help and am gaining quite a bit by reading the posts of you experienced guys. I guess one thing that can't be stressed enough is a good presnap routine. Thanks.
John