I was listening quake 2 soundtrack and song called "showdown" sounds like it's from a witcher game. Is this true or just coincidence?

For reference
http://www.youtube.com/watch?v=jY6yBTYxLko&t=25m15s

It doesn't seem like it. It's true that they used somewhat similar samples (or instruments), but in my opinion that is nowhere near Witcher music. It's just different, but I can't quite put my finger on it. Superficially it is similar but that's all. This is bound to happen because in fully tempered tuning there are only so many notes, so patterns will recur. And the number of instruments available is also finite. And who hasn't played Quake 2 back in the day?

Sidenote: And now I have to replay Quake II. Foxtrot Uniform Charlie Kilo.