Wikipedia says, "Queen of Outer Space also recycled many props, costumes, and other elements used in earlier films of the 1950s, most prominently the C-57D crewmen's uniforms, rayguns, and Altaira's wardrobe from Forbidden Planet (1956)."

I choose to believe this film was a sequel.

Thank you! I had already decided to show the Queen's face when the lyrics kicked in rather than preserve that surprise because I think they combine for a powerful, memorable moment that's the kind of thing one wants in a trailer. I didn't want to spoil even more by revealing that not all of her subjects are loyal.