Well that's bullshit. You don't get the score because "Grindem" isn't a word. Scrabble is about using your brain, and you should have tried harder to find a different word instead of bending the rules. Perhaps I'm being harsh, but when I play Scrabble, I play it hardcore.
Also, "Anti-chant drone" is a stretch. I've never heard them referred to anything other than "chant suppressors".