Not a native speaker, but to me it sounds correct in this context, since it’s about the source codes of multiple games (versus the source code of a singular game/project). Similar to how “peoples” can be a correct plural when talking about multiple groups of people.
I’m waiting in for the headline in a couple days or so:
Another hack at Gamefreak: Hackers upload fixed source codes
Unknown hackers have fixed the frame rate issues while upgrading the graphics quality to the level of the earliest Switch titles like Legend of Zelda: Breath of the Wild.