Yeah, pretty much. From what I understand, the original idea behind Goku's appearance in A Hero's Legacy was that he had died sometime after the events with Baby and was now a ghost. But when GT got canned, the writers wrote in the "Goku goes away with Shenron" ending at the last minute to permanently end the franchise by getting rid of Goku and the Dragon Balls since Toei was no longer interested in making new DB shows. But A Hero's Legacy was still suppose to be canon, so they shoe-horned in the final scene with Goku showing up seemingly alive a 100 years later so the writers could go "Hey, maybe he wasn't dead after all!", but still keep it vague about what happened to him and have his cameo in A Hero's Legacy still make some sense.