I’m not sure what previous interpretation you may have heard, but, in this case, this is very clearly a leaping foul. The foul is for leaping into the area above the frame of the body of the snapper. The snapper raised directly upward from his snapping position, without moving or leaning to either side. The defender clearly leaped over the side of the snapper (between the helmet and the left side of the snapper’s rib cage), which is easily within the frame of the snapper’s body. Leaping in a gap would have to be between the adjacent rib cages/waists of the offensive linemen, and that ‘split’ would have to be extraordinarily wide for a defender to NOT be in the frame of one (or both) of the linemens’ bodies (outside edges of the rib cage). The portion of arms raised and extended outside the frame of the body to either side do not count, and a defender ‘could’ legally leap over those. But, again, those splits would have to be extraordinarily wide for a defender to miss flying into the frame of body of one (or both) linemen.
Shaw’s review is consistent with what I have known about the rule, and is a good, correct call, in this case.
Remember, this is a player safety foul, and, when in question, it is a foul.