Taxes, black accounts and all that

The affair around the payment of 2.5 Million Euro by the German Government to the guy who sells them the names and details of 15.000 discreet or secret Swiss bank accounts, makes me think of a few side effects that this matter does certainly have.

Where is the seller located? Switzerland? Germany? Luxembourg ??
Does he pay tax on what will soon be "his" income?  Where?
Will his payment be made to a black Swiss bank account?
Or will it go to those similarly hated Cayman Islands?
Or does he know of a good laundering system?
Or is the German Government involved in a dirty deal?
Or is it all a staged affair, to scare more Germans away from Switzerland?

Will Mr Schäuble be asked to respond to all these questions?
Would my expert friend Egide Thein please take over from here??