There is no such thing as a non-US bank holding electronic USD. All non-US banks hold USD via a US “correspondent bank”, and a USD transfer from one non-US bank

There is no such thing as a non-US bank holding electronic USD. All non-US banks hold USD via a US “correspondent bank”, and a USD transfer from one non-US bank to another amounts to the sender telling their correspondent US bank to transfer to the other bank’s correspondent (US) bank, and credit the account of the receiver.