It's likely to be sauromatum venosum then, your right, that names applied to many plants, mostly aroids, including amorphs.
Lots of them could be hardy in your area but venosum is quite common.
That seed head can probably tell us a lot! It looks yellow/orange, is that all the color it has?
How long was the stem on the seed pod?
Without knowing what plants are the parents then we really don't even know what "true from seed" might mean... You could have a new hybrid, all seeds have to potential to be genetically different than the parent, even if both parent plants are identical or even self pollinated!
That said, you'll end with nice plants, I'd say there's a good chance that atleast some will germinate and a low chance of them being a new hybrid, never know... Thats the glory of seeds!
