Modify wordpress for unsupported post type

I need to create something similar to a post type, but a little bit more complex. The idea is the following:
In my website I will create a new article, adding the description and the title. Then one of the collaborators will pick the article and he will write the content of the article for Side A, then another collaborator will pick the same article and will write the content of the article for Side B.
Me, as the editor, and 2 more people will have to approve each of the two contents of the article voting 2 out of 3.
The article can only be published when Side A and Side B have content. And I don’t want Side A or Side B to be able to see what the other side wrote, only editors will be able to see both sides until it is published.
I really, really want to do this project with WordPress, can anyone tell me: a. is it possible?, b. how should I extend the post type to support what I need? c. Should I create my own BIG wordpress versión and modify core files to accomplish what I want?

Thanks in advance for any help