Personally I think that there is a logical inconsistency built right into the concept of predetermination-- which comes from the prefix "pre". The future could be determined, just like the past is, without being "pre" determined-- it might be determined in a way that is outside time. That's like the way the outcome of a historical nonfiction book is-- you are reading about people exercising free will, and you know exactly what they will do and what will come of it. When they were making those decisions, was it somehow determined that you would later be reading about them? Perhaps, but it was not predictable. Could anything ever have happened any different than it did? I can't see what it means to say that it could, but nothing is "pre" determined, we just don't know it was determined until it happens, unless it is perfectly predictable.
Spontaneity is another interesting concept-- if we see a movie in which the actor does something spontaneous in that moment, was that not a spontaneous act? Why is it less spontaneous to know that the action was captured on a film that has been in a box for a month and could not suddenly be different when you watch it?