Scam. You will probably receive a template message written in fancy English, part of which can be googled to discover it's been used a lot of times before. If a simple google check can find it, I'd imagine that people in customer support who read those messages for a living can easily see it's bullshit. On top of that that if Blizzard has solid proof that you sold gold or botted, those unban attempts are a complete waste of time and money.