...The situation with STC kinda reminds me of the situation when some of the James Bond scripts fell into public domain and Sean Connery made "Never say 'Never' Again" at the same time that Roger Moore made one of his "official" Bond films...
That's an inapt comparison, as neither group actually has the rights to use Star Trek. Furthermore, you're factually incorrect on the Bond situation, as nothing lapsed into the public domain.
Never Say Never Again had its origins in the early 60s when Bond creator Ian Fleming worked with Kevin McClory and Jack Whittingham on a potential Bond script. When that fell through Fleming turned it into the novel
Thunderball. This resulted in a lawsuit from McClory. The long and short of it was McClory received screen rights to the
Thunderball story some years after the film came out. McClory exercised those rights in order to make
Never Say Never Again.
More details
here on wikipedia (link) and
here on the blog G-BLATT's dreams (link).