Alma’s understanding of the time between death and the resurrection is more of a duality than is our modern understanding of it. We might recognize his paradise, but his description of the fate of the wicked, or the evil, is described as the opposite of paradise. That is appropriate for his understanding that there is only good and evil. That this idea doesn’t correspond to modern revelation is not surprising. It is sufficient for that earlier time, and is enriched by our modern revelation, not completely contradicted by it. Alma understood that the good are in a paradise, and that the wicked are on a location that is opposite to that.
For both those who were good as well as those who were evil, this situation will remain until the time of their resurrection, which cannot begin until after the Messiah’s atoning mission.