The motherboard is dead. This shouldn't happen so early in the product life cycle. The computer is just over 2 years old. I notice there is a battery recall on this machine. This is not right and I shouldn't have to absorb the full cost of a new motherboard!
I have gone through your Post and I understand your concerns
I suggest you contact HP Support and check for available Service Options
1) Click on this link - www.hp.com/contacthp/
2) Select your product type below.
3) Enter the serial of your device.
4) Select the country from the drop-down.
5) Select the chat or get phone number options based on your preferences.
6) Fill the web-form and proceed further.
If the information I've provided was helpful, give us some reinforcement by clicking the "Solution Accepted" on this Post and it will also help other community members with similar issue.