Why don't you give Von Braun some credit, since he came up with the plan to go to Mars back in the 1940s and anyone who plans on going to Mars will be following it? Von Braun was going to use two Saturn Vs to reach Mars by the 1980s. But Nixon canned it.
I give a lot of credit to Musk, and Von Braun, but even Von Braun was a government employee, first with Germany and then the US, standing on the shoulders of others.
If we really want to give credit to private individuals who brought about the space age, on top of that list, with no one even close to second place, is Robert Goddard.
Robert Goddard was a man who was the first scientist and inventor who made significant contributions to rocketry, and he did so largely with his own money on his own time. He only got a few government grants, most of his money came from the Guggenheim family or from his own. In 1919 he wrote a grant proposal that included a proposal to launch a rocket to the moon with a payload of flash powder that would cause a brilliant explosion which could be seen from telescopes on Earth. He was ridiculed in the press for this, an subsequently never persued publicity for his work again. This led to him not being very well known in the present day. But he continued working up until his death in 1945. He has been granted 214 patents , the majority of which were granted after his death. He was even granted patents in separate but related fields. For instance, he recognized the problem of supplying power to a machine in a zero gravity, no oxygen environment, and invented solar cells. It is safe to say that Musk, Von Braun, or anyone else can launch a spacecraft without using his work.