What kind of cream cheese filling are you using? If you are using the cream cheese filling in the pastry sleeve you don't need to refrigerate the cake. You can also use certain cream cheese butter creams that don't require refrigeration. I like Kathyf's recipe.
Yes, cream cheese buttercream must be refrigerated. The non-perishable subs will not taste anywhere near the same.
You can refrigerate your fondant. I think I have had to refrigerate every one of mine due to perishable elements. There are many threads about refrigerating fondant. The search doesn't work well on CC, but you can google "refrigerating fondant on cake central" and the information will come up. Or you can start a thread if this one doesn't answer your question.
Even though I do it successfully, there are many members who have more experience and can give better advice. If no one answers, pm me as I may not look at this thread again. I'll be happy to share.
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