This is really silly. Many thousands of actors have donned German uniforms (”Nazi” is a political party, not a military movement). Military reenactments are a long accepted pastime and certainly does not make one a sympathizer simply for playing a part.
WRONG - the Waffen SS was the military wing of the Nazi Party. It was seperate from the German Army. Unless he was forced to do this at gunpoint, there is really no excuse for this candidate's actions. He's clearly not fit for office.