I looked up these three folks, and put the information I found on this page. In short, all three have backgrounds in debate coaching and connections to Joe Biden.
However, the logs clearly appear to indicate a visit with President Obama.
Oddly, the logs do not indicate a time of day for this meeting — but one would assume that debate preparation could be extensive and time-consuming.
I expect Big Media to be remarkably incurious about this tidbit.
I wonder if the Senators will be at all curious.