The Hur'q thing was established in the Deep Space Nine episode 'Sword of Kahless'. The Hur'q were supposed to have invaded 1500 years prior and the Klingons killed all the hurq invaders and started using their technology.
Memory-Alpha:
"According to the manual for Star Trek: Klingon Academy, the Klingons acquired warp drive from the Hur'q, by capturing and reverse-engineering some of their ships when they resisted their incursions. This explained how the Klingons, despite not being focused on technological research, managed to make the societal jump to interstellar travel."
Video games are non-canon, especially manuals for video games. I don't remember it specifically being mentioned in the episode that the klingons used their technology (I assumed they were just raided, and that was that - maybe left
some technology back to inspire klingon research). But it's a little fuzzy in my memory.
Whatever - this idea was stupid. And it belongs in the pile of other one-off episode trash like Warp-10 salamanders and Spock's brain.
EDIT:
By that, I mean "conquered warriour race that stole their technology from their invaders", aka turning the klingons into Kazon, was stupid.
The idea itself, of the Hur'q, that the klingons were invaded by space invaders long ago in the past, is actually great. And deserves more exploration - maybe the fact that klingons knew relatively early about hostile aliens
led to their "Rennaisance", or even united the klingon world and made space-faring research possible?
Again, I don't remember the details. But I laways
HATED the "dumbing down" of the klingons, from a capable militaristic society to some stupid space vikings, and having them be too dense to develop warp technology on their own would be the final insult. They're warriours. They
need to research weapons and technology!