that's the best part. it wouldnt really be her as a dom, but you training her to be less submissive towards her mother. so it would be him guiding her and using Dani to make her get some control from her mother while also building her submission to the MC.Ngl, this is something I fucking hope still happens. God the idea of pounding dani's ass because he believes it's the only way he can get close to Becca would be not only hilarious, but break his heart when the blinds finally come off and he realizes he's just another tight hole for you. Although I can't really see it working without a lot of effort on training Becca up to be a dom... Which wouldn't really work considering MC's ego is pretty dominant himself.
it would also give her the excuse to deal with Dani who she has shown to really dislike due to him being a simp. so it would work on both levels.
also, it could be less the MC giving her dom on him, and more training her to dom Priscilla instead.