My guess is that that hole is maybe 4 to 6 feet in diameter! Now recall that the diameter of a Mk 48 is a bit less than 21 inches; in my opinion the claim is bogus. A more likely explanation is that something circular that was welded to the inside of the outer hull was torn away by the force of the torpedo room explosion/implosion.
Good estimate. The actual size of the three diver access holes cut in the hull with the abrasive water jet was 48":
"In all 11 cuts were made on the Kursk using the Abrasive Water Jet cutting system, 3 pressure release holes in the 400 bar (5800psi) ballast air piping system, 4 through the outer super structure, and 1 pressure release hole and 3 diver entry holes in the pressure hull."
"...the 1.2m (48) diameter access hole through the 50mm (2) thick pressure hull being completed within an hour"
I hadn't thought of that but looking at the bending to the left of the hole, that would make sense.
In any event, I don't know anything about navel explosives or submarines but I have to assume that a torpedo couldn't enter a hull, explode to the right and leave it's entry hole and everything to the left intact.
It could also be post-disaster, i.e. from the salvage operation to get her back to the surface. Anyhow, it seems to me that any entry hole would be obliterated in the subsequent explosion and that the damage would be somewhat symmetrical to the impact location. Judging from your picture, it looks as if all the major damage is forward of the hole.
Also, I don't see the Russians giving us a pass regardless of how much debt we forgave. The bad PR for us would have been too tempting.