You can definitely try it and let us know how it goes.
Personally I would be tempted to take dehydrated apple slices, sugar, and spices along with the dry ingredients for the crisp topping and assemble and cook it in camp. add boiling water to the apple mixture and let sit until rehydrated and then add the topping and bake in a reflector oven or outback oven or however you do it.
Well I made up a batch of apple crisp and ran half of it through the dehydrator. Think I should have sliced my apples thinner as it took almost two days to get it all to dry up good. Sliced them into chunks rather than thin slices. I made it per my wife’s recipe but used Splenda instead of sugar as I have to watch my sugar intake. I put some in a bowl and poured boiling water over it and let it sit for about 10 minutes. Tasted real good but think this method may work best for my solo instead of our group trip. The Sherpa sat and ate it just as was and said he really liked it that way. Said it was like apple granola.
Think for the May trip think I’ll slice the apples and dehydrate them and make it in the GSI Dutch oven.