Unfortunately, even with the height you were shooting from I would have to say it's very unlikely that your arrow ricocheted off a rib and only penetrated fat and hide, especially if you have blood on the fletching and saw the arrow sticking out of the deer. Chances are you hit him exactly where you thought - a little far back and maybe a little high. Quite often a hit like that doesn't bleed well because there's only one hole where the arrow entered, and no exit hole. I would be willing to be the arrow went in and then got pushed back out as the deer ran through the brush. The fatty or slimey feeling on your arrow could very well be from a gut hit, even though you think you should have at least gotten one lung. That rear lung/liver/diaphragm area gets pretty tight in there and what looked like a good shot at the time might turn out not to be that way in the end.

Just becuase you didn't have a great blood trail doesn't mean the hit was non-fatal. I've double-lunged deer before that left little to no blood trail at all, and I've single-lung/liver shot deer before that bled like crazy. I think it really depends on exactly what veins and arteries were cut when your arrow entered the animal. Sadly enough, from what you describe it sounds like a fatal hit, just a bad blood trail.