They were shot on 35mm but as far as I know, those elements were then composited in video, which is why they had to, and could, be recomposited digitally for the HD version. I bet the elements shot directly to video were the ones that had to be recreated with CGI.
As to whether TNG is available on Netflix in Slovakia, I have no idea, though I don’t see why it wouldn’t be, if it’s available here in the Czech Republic. And if the article says that the fixes were done specifically for Netflix, I’m sure that’s what you’d get.