I saw some people talking about this and the 2 things that stood about to me were 1) the name Slave-1 was never in the movies. It was added for merchandising. In fact, a lot of ships and other characters/creatures names were added to the toys because otherwise Lucas/Kenner couldn't copyright the toys. And 2, )they've been giving generic names to a lot of the newer LEGO Star Wars sets. The Gozanti cruiser became the Imperial Assault Carrier, Phoenix Home from Rebels became the Rebel Assault Frigate, and the Arquitens cruiser is now the Imperial Light Cruiser and the list goes on.