It's like we never hear Bi-Han and Kuai Liang talking in Chinese, never hear Hanzo Hasashi talking in Japanese and never hear Tomas Vrbada talking in Czech (there may be more characters with different languages, I forget). They probably have the code name aliases like Noob Saibot, Sub-Zero/Tundra, Scorpion and Smoke out of respect for their nationalities ways and true traditions (notice these locations are all on Earthrealm).

Sounds like something Klingon, although the spellings would look different.

Kung Lao practically killed him (results of this are seen in MK4 Gold), so chance is he's talking payback.

Recently (or at least in the recent year) Shawn Kittelsen, the writer of the MKX comics, said it was fun working with NRS to make the tarkatan language for MK11. I think it could help asking him.