Is the Arcturian extraterrestrial, Maria Orsic still alive and still working within the military industrial complex to serve the Extraterrestrial Alliance covertly?

As you suspected, she has retired from the scene. This is for reasons of personal safety and security. Having been present all through the Nazi era and beyond, it was deemed desirable for her to fade into the background and allow others to take over, so she has returned home. She is still among the living but is no longer collaborating with the government or military operations collaborating with the extraterrestrials.