Hello,
From my understanding, the key you provided appears invalid to Windows/Microsoft systems.
In that, as this needs help from HP regarding the key itself, I would strongly suggest you call HP and explain the situation and see what the agents can offer you. This way you can keep a track of the issue.
Although this is HP official forum, you do not speak directly to HP here and people volunteer their time here in the forum.
Generally speaking, as far as I know the call itself should be free and after you explain your case and situation, the agents will provide you with options.
Please, keep me posted.