What is the difference? The soldier was not ordered to carry out a MILITARY COMMAND, something that was a matter of LIFE AND DEATH. He was not even commanded to tear down a "settlement." He was ordered to participate in a social entertainment that involved a violation of the tenets of his faith. Would you feel any differently if a BAPTIST soldier was ordered to dance, or if a MORMON was ordered to drink a beer.
We will not mention the uproar that would ensue if a MUSLIM soldier was ordered to do either of these things.
The question is was it a lawful order. If it was not, he was right to refuse it. If it was a lawful order, he was in the wrong, and should shut up and take his punishment.