According to the Florida Aquatic Nurseries description, they are one in the same plant.
Cryptocoryne wendtii 'Mi Oya' is a very vigorous Cryptocoryne that will grow equally well as an aquarium plant or as a terrarium plant. Red wendtii Cryptocoryne as it is more commonly known is one of the most popular varieties of Cryptocorynes in the aquarium trade. A great plant for the beginner it will tolerate almost any condition from low to high light and does not need fertilizer or CO2. Cryptocoryne wendtii 'Mi Oya' will thrive under medium light and regular fertilizer applications.
http://www.floridaaquatic.com/aquarium_plant_cryptocoryne_wendtii_mioya.html