If there was no sea wall they would have missed the runway by 50-100 feet or so, and probably landed just short.
Well, not exactly, the aiming point is somewhere 1000 feet down the runway so they were already that much off. So they could have a sub-par day and land say 500 feet down the runway, or even make it a very, very sub-par day, touch down say 200 feet downstream from the sea wall, the airplane would still be in one piece but them "missing" the runway by over 1000 feet that's pretty extreme, landing is not like shooting darts into a target, you miss or not, landing is a prolonged event and you have multiple chances to make corrections, they never took advantage of them.