Wossner black wings is roth x anitum, RHS recognise this as a species for registration
Johanna burkhardt is roth x adductum
Unfortunatly the problem is many don't recognize anitum as a seperate species but rather as a variety of adductum.
The AOS refused to accept anything with anitum in it (as anitum is not listed by CITES) for judging so most people used roth x adductum var anitum = johanna burkhardt for showing. This created the mess these two are now in.
You have a similar situation with the cross Chou-Yi Anigode ( godefroyae x adductum) and Hung Sheng Tango (leucochilum x adductum). The Hung Sheng Tango I've seen for sale were made with the anitum. But, RHS puts them as synonyms...
I'm not even sure if either cross were ever made with a "plain" adductum.