Fist of all game programming isnt about just a single language like you pickup java as your base n go on making a game.
Game programing is just one of a department in game development team which comprises of programmers, sound engineers, graphic artists, debuggers, modellers, hardware testers and so on..
Even in programming its a vast line.... core coding, sound, interaction, AI, texture, encode decode, linkers etc.
So as you see the entire programming isnt possible by a single person but you do get a chance to work on all the above depts. accordingly.
Hence, your friend can pick up any language of his choice and become a pro in that with a strong logic development skill and ultimately try in any gaming company. His designation will be in software development dept. But they look for hell lot of experience and that too on live projects.
Thus as per qualifications people are placed acordingly. And if you are multi qualified then you have more options to choose from.
My friend is certified animator with tons of experience and also a pro in java and c#. And he is going to apply in biggies like EA Games, Eidos Interactive, Rockstar Games etc...