When Fleishman first discounts Pierre being a body, he insists such preservation doesn't occur in nature, but Mammoths have been discovered perfectly preserved with blood in their veins and undigested food in their stomachs.
When the frozen body in the ice block is standing in The Brick, it is very clear by the conversation that they will be storing him in the walk-in freezer. But later, when they show the body now in storage, you can see lots of dry goods, such as bags of pancake mix, sitting on the shelves. These would not be kept in a freezer. In addition, you can't see the breath of anyone standing in the room, so it is quite obviously not a freezer they are standing in.