Their actions would be legal, lawful and legitimate under the Uniform Code of Military Justice if they had no knowledge that your command was unlawful.
Military discipline and effectiveness is built on the foundation of obedience to orders. Recruits are taught to obey, immediately and without question, orders from their superiors, right from day-one of boot camp.
Military members who fail to obey the lawful orders of their superiors risk serious consequences. Article 90 of the Uniform Code of Military Justice makes it a crime for a military member to WILLFULLY disobey a superior commissioned officer. Article 91 makes it a crime to WILLFULLY disobey a superior Noncommissioned or Warrant Officer. Article 92 makes it a crime to disobey any lawful order (the disobedience does not have to be “willful” under this article).
In fact, under Article 90, during times of war, a military member who willfully disobeys a superior commissioned officer can be sentenced to death.
So the men under your command should obey your orders if they have no knowledge of the fact that you “grabbed some rank” illegally. The accusation that you “grabbed some rank” is not good enough, there would need to have been an official finding to that effect.
So, let me get this straight: "just following orders" would be a valid defense in this case where the orders are, you say, unlawful.
That's reminiscent of the "It's ok when we deem it ok" style of governance which is characteristic of tyranny.
Military members who fail to obey the lawful orders of their superiors risk serious consequences. Article 90 of the Uniform Code of Military Justice makes it a crime for a military member to WILLFULLY disobey a superior commissioned officer. Article 91 makes it a crime to WILLFULLY disobey a superior Noncommissioned or Warrant Officer. Article 92 makes it a crime to disobey any lawful order (the disobedience does not have to be “willful” under this article).
Question: How can an order which is to follow the Constitution (Art 4, Sec 4, in this case) ever be unlawful?
So the men under your command should obey your orders if they have no knowledge of the fact that you “grabbed some rank” illegally.
It's not illegal to grab some rank. The USSC has even struck down law prohibiting one presenting oneself as having some military experience that one did not actually have. (See here) As ABC summarized it: "In its 6-3 decision, the Supreme Court justices said today that as written, the act is too broad and ignores whether the liar is trying to materially gain anything through his or her false statement, which would be more akin to fraud."
The accusation that you “grabbed some rank” is not good enough, there would need to have been an official finding to that effect.
So which is it: are thees soldiers who are compelled upon penalty of death to obey allowed to question my legitimacy or not?