Late update, but figured it might help some folks here. I submitted a formal notice of dispute through Microsoft's arbitration/dispute resolution department. This got their attention, and someone from that department authorized a free exchange. Currently typing this on my new-to-me/refurbished, non-cracked SB3. I'm guessing that faced with paying the costs of arbitration, they figured it was cheaper to send me a replacement unit. Can't believe it took this much effort.
Did you send the notice via a letter by mail? Or is there a way to drop them an e-mail?
This because I am from the EU, I can send the letter without a problem, but a e-mail address would be faster :)
Edit: I did sent the letter via the mail to US. Hopefully they reach out soon to me.