I lost one this year that I shot at last light as I went to the truck to drop my gear and give her some time when I returned it was a blizzard and I couldn't see more than 10 yds when I returned the next morning to try and find her the yotes had eaten most of her. I never thought about saving the backstrap that is a pretty good idea though if it happened again I think I would take those and leave the rest.
You made the right call though let mother nature take care of the rest at least you know there will be good yote hunting there.