Possibly aiming down at 30 degree? angle, was not the best bet whilst the Captain was inside that self contained lifeboat.
How about a seal (or two) hanging off the back of the LB, little loops all over, gun of the day in two hands (they would be secured via clips so hands free) ear piece radio in place. "On three, One. two, three!" the one with the AK, history. The two in the hatch, shot from the water, from each side of the hatch. All shots would be frangible 9mm.
Remember bits of body and bone can be lethal, why use a 2700 fps .308 into the skull, when a burst of 9mm frangible would do the trick, especially from sea level aimed up.?
Wondered why no video? That's why, seaborne assault, Navy Seals live in that medium. Do you think they want their tactics played live on the 50" flat screens in Somalia. You can be sure of one thing, how ever that wee scene was played out, it will not be on Utube any time soon.