It's the front end (top). I was told by a few people (including the guys at arbor) that trying to get it fixed to use it would just be a temporary fix and it'd end up letting water in and ruining the whole thing.
people cut snowboards in half and make them into splitboards all the time. as long as you seal it its fine. its never going to last as long as if it wasn't cut, but it makes way more sense than throwing it away or not using it.