I think the problem you're having is that you must be off the major shipping lanes and you are in a very cold area. Sachs uses priority mail, but that may take longer to you.
Have you offered to pay for overnight shipping?
You can keep fiddlers alive by offering simple things like fish flakes, fruit, and (!) air popped popcorn. I kept one for 2 years on this diet. They don't have to be submerged, just sand and "pool" of water. If you're using them quickly, 10 or 12 can be put in a turtle bowl with a stone in the middle as an island.
not sure how revelant this is, but i get snails and hermits at livebrineshrimp.com. i just got an order in yesterday and many of the hermits i got are bigger than i thought they would be, though they are out of the cheaper snails at the moment.. but its pretty dang good and the prices are excellent
Alright then, i figured it didn't really matter since they don't live under water but i just wanted to make sure. They seem simple enough...i just hope my octopus enjoys them. I've only gave it marine ghost shrimp, krill, silversides, and crayfish. It doesn't eat the blue legged hermit crabs i got it and the turbo snails so i hope he takes to the fiddlers. Thanks for your response!