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.
Only if ABC reported that the names on the list had done something untoward. If they were to simply report the names on the list (as gathered through the FOIA), no harm no foul. I would tend to believe (at this point) that the decision was due to the lack of players on the list.
I assume (yeah, yeah, never assume) anyone here is free to plow through the records and report out; how could ABC or any other venue get exclusivity?