I ordered seeds from them back in 1979. I had one come up. I donated it to the Fruit and Spice Park in Homestead in the early 1980's.
They've had only one tree for years and have been getting fruits and seeds so I can't speak to their needing cross pollination &/or being either male or female.
Now if I can just get down there to donate 2 butter trees Bassia latifolia.