The translator is wrong:
1. That isn't a crucifix, it's a cross. A crucifix has an image of a crucified Christ on it. That doesn't.
2. An upside down cross is called St. Peter's cross and for the last 2000 years it has symbolized Christian humility before God. An upside down crucifix means nothing.
3. St. Peter's cross is not the symbol of Satan. A seven headed dragon is.
In the late seventies a b-tier horror movie came up with the idea that an upside down cross must mean the opposite of Christ, so they used it to represent evil. A few idiot metalhead bands picked up on the idea in the eighties, and it has since spread through the American edgelord community. That still doesn't change the fact that churches worldwide have upside down crosses all over the place, because they mean humility before God. It's like if Nazis decided to show they hate Jews, by wearing the Star of David and swearing of pork.