I am on a time schedule. I am buying 14 ready-made cakes from the grocery store to make 7 double layers with sleeve filling. They come frozen. The sleeve filling also comes from the store. Using cherry and raspberry. Can I fill the cakes, stack them and crumb coat with buttercream icing and them put them in the freezer until ready to ice. And then I was going to put them in the fridge for two days until the event. The final icing is also buttercream.

Simple answer: YES
I have done it many, many times. The fillings you are using do well with freezing. Now Bavarian Creme? not so well.
So hurry up and get those cakes filled, crumed - and if you like even finish- iced (final coating of b'cream) before fz'ing them.

I can totally complete the cakes, icing and all and freeze them?

Anyone answer this???