Iran probably would have preferred dollars. The reason dollars weren;t used was to avoid a direct violation of "no ransom shall be paid in dollars" law, plus sanctions that supposedly inhibit making regular bank transfers DIRECTLY from a US bank to an Iran bank. The sanctions may inhibit indirect transfers too, but obviously the government isn't going to prosecute a bank for violating a sanction, when it is the government itself ordering the transfer.
The wole thing stinks, but nothing is going to happen on account of it. Well, other than our money is going to be used to blow us up. The government will then confine us for our own protection.
How does the U.S. govt. get 400 million in foreign currency and gold bullion anyway.?
Does Valerie Jarrett get into the big Chevy white van,snag a healthy waiter or white house yard guy and say come on we got a job to do? How does that work?