I could be taking your statement in the wrong way, but if you suggest a crease created by a fold is a potential weak spot,.......Not on any LE I have ever seen.
I even have a 2013 Best kahoona that I got off of Ikitesurf (before you had to sign up as a registered user) that was dragged across rocks on the LE and has cuts about 50% of the way through the leading edge. I flew and crashed it before I realized it was damaged (canopy was almost new and there were less than 10 sessions before I bought it). It never blew up.
That said, it is not what I would consider an ocean worthy kite.
If the OP is telling the truth, then it is a warranty issue. But no kite company will warrant this as they will all parrot the feedback on this thread you are getting - "its your fault.......even if it isn't".
Remember, warranty claims (like car warranties, or appliance warranties) are paid for by companies that make more money by denying your claim. I don't think there is any kite brand not operating under this premise.
So don't buy Naish anymore if they deny the claim. It is the only power that kiters have over the corporate kiteboarding machine. Maybe some kite brand will come along and realize that there are kiters out there actually looking for a brand with a warranty department that is not into denying every claim. And hopefully, in my lifetime, some kite company will come along and not care if they get defrauded on one or two kites, so long as they never deny a legitimate claim.