Vladimir,
Thank you for posting your thoughts about Moravsky Div. I also have some suspicions about Moravsky Div similarity to Stupice.
Also, I will not be surprised about name change by Russian seed vendors. They like 'catchy' names, and „Моравское чудо“ is a catchy name in Russia, much more marketable than 'Stupice' or 'Stupicke'. There it is all about marketing (and profits), not about historical accuracy or proper attribution.
I can do a long rant about variety names changes in Russia (some may say 'creative translations'), but this is a separate topic. We are guilty about the same here, but not to that extend as in Russia. (I hope! )
Tatiana