I came across this word in the MMO Lotro and I suspect it may be a German word, but I'm not sure. If it is, I'd love to know what it means. My poor guess is something like "forest defender."
It's not a common noun (= normal word). In the realm of its fantasy world it's probably a proper noun (= name). It was probably chosen to evoke precisely the sort of association that you're experiencing. Please note, however, that while "Wald" is a German root meaning "forest", "gard" isn't, so the desired effect really only works on speakers of English with a vague familiarity with German - not on actual speakers of German.
Alternatively, "-gard" is an old Germanic root meaning "yard, enclosure", as in "Midgard", and this may also have influenced the choice.
It is not a German word according to the official dictionary (The "Duden").
Is is not a german word I've come across, and it is not in any reference material I have access to.