If your dropshipper can prove that the 'Monster Beats Studio by Dr. Dre White DJ Headphones' you are buying from him are authentic and he can provide you the necessary documents - I guess it would be fine to list it.
Basically, the two main things about listing branded items on eBay are - (1) the item is authentic and (2) You have documents or receipts to support the authenticity of your item.
I did a similar search for a request posted in support and I ended up in the same place as Irene. So best check the authenticity of the one being offered by your dropshipper.
Hope this helps :)