Just so I understand this. Your hives went into winter with some honey in a single deep and a half full super? Additionally, did you have a top entrance? If you had insulation on top and wrapped the hive you are creating a environment where there is going to be a good amount of moisture build up inside the hive.
I suspect your bees either starved to death or got wet and cold which killed them.
I send my bees into winter with two deeps full of honey about 150 lbs worth and throw patties on whenever the weather is warm enough to open the hive. Also if you are going to wrap your hives you really need a way to ventilate out the top.
Hope that helps.
Life is tough, but it's tougher when you're stupid.Ē John Wayne