Somehow, I don't think we're getting the entire story. I've never heard of windshield crack protection, but not saying it doesn't exist. First thing you should do is read the paperwork.
How did the windshield crack? Does it fall under the actual warranty of this Permaplate?
Not sure if this is the same PermaPlate, but here's a link to the PermaPlate website and how to make a claim.
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