Annual ryegrass and winter rye are very different. Annual ryegrass is not a preferred deer food, and it will not survive the winter. Annual ryegrass is great if you want a fast growing lawn, but there are better options for a food plot. Winter rye is a cereal grain, like oats. It will survive your winter, and stay green all winter. Winter rye will become more attractive to deer as the temperature drops, and provide early spring feed as well.

My opinion would be to return the ryegrass and ask for winter rye.