What were the lowest temps ?
What temps are you working with in your area ?
For puriens I have seen a mature fruiting tree in Bellingen NSW, inland from Coffs Harbour.
That would be cool winter subtropics, and not just for the hippies that live in the area.
I am fairly sure it is grown at the Sydney Botanic Gardens, well outside the tropics.
I would say the tree is a tall understory plant that likes shelter when young.
I have collected seeds in Cape Tribulation area, and seedlings do ok in Victoria (Citrus growing region) in pots under shade cloth.
Didn't like frost but grew back their leaves. Cool nights not a big problem, but will slow growth.
D. jerseyana didn't defoliate under the same conditions.