GM banned my friend because I lent him gold

In December I took a short break from wow as I was moving. I passed my friend 30k which was all the gold I had saved up so far, via mail.

Yesterday, I decided to resubscribe. My friend passed me back my money via in game trade.

About 15 minutes ago, my friend just had his account banned for 72 hours. The email cited "Abuse of economy". He is a clean player and the only possible explanation would have been the gold he passed me.

Now, I'm no fan of gold sellers and I think GMs should definitely ban these people. However my friend was wrongly banned, and the GM didn't even whisper him beforehand to give him a chance to explain the (admittedly) somewhat suspicious trade. Regardless, the record of me sending the 30k in the first place is certainly there.

Firstly Blizz, please unban him ASAP as he did nothing wrong. Secondly, while I appreciate the intentions, try not to ban any more innocent people when it can be so easily avoided by simply whispering first.