Nissan themselves say that the issue is down to wear and tear, so this insurance policy wouldn't pay out for that. It's not a warranty, it's meant to fix things when thieves try and steal your car. Tbh every single insurance policy covers the exact same thing anyway, which is general damage by vandalism or theft, so whilst it's a nice idea any one buying a JL policy on the basis of claiming for this is going to be sorely disappointed methinks. Plus it's going to affect your claims history, something most folks want to avoid.
Unless, of course, you could somehow lose the entire steering lock mechanism, as it clearly says that it'll replace it in that case...