Maya is slowly but surely getting her shit together, but Josy is unraveling, and is now the biggest threat to the throuple's success. So even if MC did manage to convince Neil, I don't think Josy's problems would go away.
As for Bella, there's still the small details of her being married on paper and being MC's teacher. I think for Neil, that would unfortunately override his usual advice of "follow your heart" (like on the throuple path). And you meant "has no children
yet
Sage was right though, Zoey was lying in wait and ready to pounce. She didn't want to be "just friends" anymore. Sage and Jill trust MC, but like Sage said, "she doesn't trust her."