She didn't beat them is just your opinion, what matters is that the fight record was set as 1-0 Carla vs Marina, theres no getting around that. It won't make sense to run back another split decision fight to replace the Carla Rose split decision fight. These fights sucked, which is why Weili is getting the shot.
The UFC is very clear about how rematches work, if you have a fun match and theres a market for the rematch, you get it. If your first one is a stinker then even if it makes sense ranking/matchup wise you won't get it. Rose vs Joanna 1 was fun, it ended in a cool finish, left a lot of questions, run that back. Same for Rose vs Weili. Weili Joanna 1 was an all time great, run that back because thats guaranteed fireworks, and it delivered.
People who are promoting the idea that Carla vs Marina makes more sense than Carla vs Weili is forgetting that the first fight sucked and its already in the books, nobody is gonna pay to see that again. Thats my point. Just like Carla vs Rose even though it makes more sense than Carla Marina, they are not getting booked for the exact same reason. The only fight that is both justifiable in terms of rankings and bringing in the viewers is Carla Weili, the other ones aren't even close. If Rose Carla didn't suck so much that would have been the fight to make, now its basically impossible. Rose would need to finish some other girl or Weili would need to be the champ and not Carla. If you want your girl Rose to get an "immediate" title shot, have her sit out until Weili Carla, Weili wins, Rose fights Weili for the championship.
Anything short of that timeline Rose needs 1 more fight in between, probably against Marina actually. If she finishes her or wins dominantly she would get next even if its vs Carla if Carla wins vs Weili..