I'll mark this as a community wiki since I'm summarizing a bunch of comments folks left.
Who owns the mistake
In your description you said that the sender put in an incorrect account. You as the receiver have never gotten the money, it was never yours, and the sender is still under the obligation to send it to you.
It is not your problem (technically), it is the sender's. If you sue the sender you'll win - they didn't pay you.
Who can return the money
The actual receiver can return the money to the sender. The sender can sue the actual receiver if they refuse and will win. The sender's bank can attempt to reverse the transaction and claw the money back based on the mistake (might need the cooperation of the receiving bank, but no need in the cooperation of the receiver themselves).
Again - not your problem, the sender's.
What can you do
Nothing, other than demanding your money from the sender, since you're still owed. Practically - not much. If it's not a significant amount of money compared to lawyers' fees, write it off.
- Foreign contracts are hard to enforce. It will be expensive to sue the sender, even if it is a genuine transaction and that person really exist.
- Wire transfers are notoriously hard to reverse (by design), so the sender will try to shift the responsibility to you even though its their mistake.
Is it a genuine transaction?
This smells like a scam. Someone sends money to you, but it gets lost, now you have (have you?) provided some goods or services and are sent to chase your tail for payment that you will never actually get.