where they will put all the money when they sell those btc?
For this particular auction it will be held by the USMS until the issue of whose money this actually is can be resolved in court.
If the court rules that the money belongs to Ross then it will go to the bank of his choosing. If the court rules that it is the government's money then I believe it will go to the US treasury.
Hasn't this been decided in favour of the government?
If the court rules that the bitcoins actually belong to Ross, then can't Ross ask for his bitcoins back (rather than the money realized through their sale). If the price of bitcoins goes up to $1000 and Ross asks the feds for bitcoins, it would be fun.