In the Grand Canyon, generally, the more remote the camp, the less trouble with small furry creatures. They, especially the squirrels, can be particularly brazen at places like Hermit Camp and Monument Camp. I've never camped at Indian Gardens but I suspect that there are active squirrels there. Personally, I favor more remote locations in the Grand Canyon but often have to camp for a night at one of the more frequented sites en route.

You will definitely want something to protect your food. I use an Ursack and hang it out of reach. I use an Ursack because that is what I have; I have been told that it is not mouseproof however. Others use metal mesh sacks such as the Ratsack with success. I have not heard of the Outsack before but assume it is a Ratsack with a different name. Do use something though, the prowling critters range from ringtail cats and ravens to mice; all will go after your food. I have personally watched ravens unzip pockets on a pack and remove the contents looking for food. A ranger I know feels that the ravens are smarter than a lot of the hikers he meets.