the parties involved aren't going to say anything incriminating...they now have their story and they'll be sticking with it.
the ONLY potential to make something of this is to put Sestak under oath to see if he repeats the BS story. If he does, it's over.
If he tells the truth...then you can put others under oath...but they'll lie and it'll be a "he said/he said"...and won't be prosecutable.
I'm wondering if it's just better to let this lie and let folks wonder...
No way. Asking a candidate to stop campaigning for no value is as stupid as it sounds. The Obama WH committed an egregious act of Chicago politics and Sestak sang. This is a felony for obvious reasons. The law specifically addresses primaries.