Hi there
I'm just wondering what your end result was with this issue. I've owned my Envy x360 for not even 4 months, and my screen just randomly cracked on its own 2 nights ago. I contacted HP Support, and have been given the same run around. I can ship my computer to them for a free analysis, but if they decide the damage is "accidental", then I have to pay $99 to get my computer back, or over $400 to have the screen replaced.
Clearly this issue has been ongoing for at least 5 years. If you do a search on "cracked screen" HP Support (where I found your message), there are 41 web pages filled with messages from other people that have experienced this same issue.
This is NOT OKAY, and HP needs to step up and accept responsibility for creating faulty products.