I thought of something today.
We had come to the conclusion that the attempts made to alter a significant moment in history (i.e. stopping the shooting down of the U2) in order to prove the success of the Quantum Leap experiment were essentially pointless - unless there's a way for the committee members to experience both timelines, there's no way that even if history was changed, they would actually notice it.
But it actually IS possible to prove, in more than one way...
1. Using a time capsule - have Sam put important documentation or a recording of himself explaining the project, bury it but let Al know where it is, then Al take the committee members to the site and dig it up.
2. Have Sam write a letter (or record himself discussing the project), send it to the post office, and tell them to deliver it to the committee on the exact moment that they are sitting discussing the funding of the project.
I'm sure there are other ways it could be done as well. Obviously the key is to make sure that what Sam wants them to know is able to reach the committee in their time without it having been tampered with or the possibility of it being fabricated