I would again suggest calling the vet. I'm a little surprised that they took the bandages off so soon. When I got my cat declawed (before I knew what it was) they instructed me to keep the bandages on for at least a full week, and his poor little paws still got infected. That is what concerns me most about your situation with the litter and unbandaged paws. Obviously litterboxes in general are going to contain bacteria, and especially if he's got litter stuck in his open wounds, I would be very concerned about possible infection.
Please keep a close eye on him, in any case, for signs of infection and dehydration. Is he on pain management meds? Watch for lethargy, additional sensitivity to the paws, unwillingness to walk to eat, drink and use the litterbox. Check him for dehydration using the "pinch test" - gently pinch the skin up on the back of his neck (like scruffing him, but only pinch hard enough to pull the skin up from his neck). If the skin snaps back quickly, he's fine. If it kind of sticks in place for even a little bit, he is or is getting dehydrated and needs to be taken to a vet right away.
I don't mean to scare you, but I almost lost my Trent because of the infection in his paws and dehydration. So it is a serious complication to watch for.