Yeah man. That’s why I stopped really taking midsole jobs unless it’s the back of a Jordan 3. Jordan actually changed the paint/process on what they do for mid soles so it will last longer. Adhesion promoter might make it last a little longer
Unfortunately midsole are going to crack. The material is not meant to be painted with acrylic paint. Even Jordan midsole crack after awhile. You did all the right steps fam