Eurodollars are dollars held in non-US banks, which are nonetheless banks and therefore subject to the banking regulations of their respective jurisdictions.
The Fed can do that any time they want by buying bank debt with newly created dollars, which effectively socializes the risk in the banking system, so it doesn't fail, hopefully at something resembling market rates. The Fed then runs the risk that they don't get paid back instead of an individual bank, but the modern Fed cannot fail, that sort of thing can only affect the currency as a whole, by weakening it generally speaking.