I consider the people that you mentioned (Flipper and Senti) to be experts in the trial and they both are convinced of the success of the trial.
I bet if you asked them they would say they are cautiously optimistic.
I don't think they would say they are "convinced" the trial will be a success.
having said that, LOL, I think the trial (as modified to use a BS endpoint) will very likely be a "success".
A "success" lacking scientific validity though.
"A Successful trial is one that provides a reliable answer to the question it addresses." Tom Fleming
So, with the modification to using a historical control, and Fleming's definition, I would say that no, the trial will not be a success (because the answer will not be reliable).