I know they were buddy buddy back when Eminem was in the peak of his drug addiction:
I know Cashis was always on Eminem's nuts in interviews and the same with Eminem. Eminem was always talking about how great Cashis was. Then when he had his near death experience it seemed like Cashis just fell back and eventually was released from Shady Records. And Eminem in Going Through Changes mentions that drug dealers hung around him like yes men. So who else could have had a better chance to be in the studio with Eminem at that time than Cashis? And Cashis was always talking about how amazing Eminem's music was at that time with the infamous King Mathers LP we never heard. I just think it is strange that Eminem was so high on Cashis and then he just fell back completely when Eminem sobered up and started his comeback. Maybe Eminem just had to cut ties with him because he couldnt be around all of it anymore, especially if Cashis himself was using the same drugs/pills/alchohol.
I've thought about this for years and maybe it's a crazy theory, but some of the facts add up. I may not have gotten everything right, but I think it's a great topic to discuss.