I don't think it's material which department in citigroup owns which account. Citigroup is responsible for all the money as a single entity.
When you work in a company and pay a supplier, you don't get to chase the supplier and ask for refund saying you cut a check from the wrong company account. This is down to your company, it's your company problem.
A company is a single entity, but a bank is representing many entities, so I do think it matters which entity the bank was representing at that point in time.
If I overpaid a contractor by mistake, I don’t think that contractor should get to keep my money under the logic that somebody else who uses the same bank also owed that contractor money.
Your contractor contract should have a clause to specify that he must return overpaid money. My employment contracts all had that. This helps dealing with this sort of issues :)
Citigroup, Revlon and Bridage certainly have long complicated contracts on that loan, that should cover what to do. Well, I really hope they thought of covering the basics while drafting a billion dollar loan.
If I owe you money and John Smith knocks on your door, hands you a pile of money, and says “this is from bradleyjg to pay off his debt” I think it is entirely reasonable to rely on that representation. You lent money, it was paid back by the borrower’s agent, the transaction is over.
Except they didn't say that. They sent it by accident. And there's decades of case law siding with banks against "bank error in your favor" situations.
There's no indication in any reporting that the money was sent with a note or memo saying "this is to pay the full Revlon debt". To all known facts, they simply sent the money.
When you work in a company and pay a supplier, you don't get to chase the supplier and ask for refund saying you cut a check from the wrong company account. This is down to your company, it's your company problem.