Sand in deep end

I doubt a shop vac will be of much use as the canister will fill too quickly and the float will shut off suction. I thnk your best best short of vacuuming to either waste or filter would be a stand alone pool vac like the Blaster or similar. You'll have to empty often and be patient but it will work. You might try "sweeping" or scooping some of the sand up first.