so perhaps a different album called "Greatest Hits" was released in the US? It's not unheard of (or even that rare) for artists to release different track lists for the same album in different regions. Mansun had a different track order for "Attack of the Grey Lantern" in the two countries, and replaced "Stripper Vicar" with "Take It Easy Chicken" in the US.
The confusion here is that "Queen's Greatest Hits" in the UK is this:
https://www.amazon.co.uk/Greatest-Hits-Queen/dp/B004FE2N48/ref=sr_1_1?ie=UTF8&qid=1467731570&sr=8-1&keywords=Queen+greatest+hits
so perhaps a different album called "Greatest Hits" was released in the US? It's not unheard of (or even that rare) for artists to release different track lists for the same album in different regions. Mansun had a different track order for "Attack of the Grey Lantern" in the two countries, and replaced "Stripper Vicar" with "Take It Easy Chicken" in the US.