What would have been the basis for this “huge lawsuit”?
I don't know, you would have to ask the attorney. If the client's name and number appeared in the DC Madame's phone records, it doesn't prove anything other than a phone call occurred. If it was innocent or lawful, I would think that ABC may be risking a defamation or libel suit.
public accusation of a criminal act.
It is a year one law school no no.