Well subpoenas all around then.
Subpoena
A subpoena or witness summons is a writ issued by a government agency, most often a court, to compel testimony by a witness or production of evidence under a penalty for failure.
Yeah that’s really a great idea. So let’s subpoena everybody, have them sit at the table and then ask them all kinds of questions, which will be answered as you already know, by the witness saying “I do not recall.”
Then what?