I meant the edit I put at the bottom of my post (like an hour ago in this thread) where I posted the problem. Here is the other thread where I asked the question about instantiating two classes with different stores. From Googling around, it seems to work for other people, but I don't know if it's because I am doing an MVC app with PR4, or I am missing something else or what.
I was going to toy around with having listeners on the actual grid view. Maybe a beforerender listener that allows me to fire a method in the controller that creates the store there. Something like that.
Keep in mind, I am putting these two grids in a carousel, so that may have to do with it still sharing the store somehow. Just need to figure out what's causing it to share one instead of using the ones being created in the constructor.