User blog comment:EmpyreanSmoke/Supernatural Q&A/@comment-79.115.73.90-20150814153903/@comment-24834479-20150819001244

All I can say is that things will be explained this season.

There hasn't been a lot of discussion about this, at least not while I was in the writing room. I'm not sure how the cage works, or how Catsiel was able to get Sam out.