Before Smash, Hal did Kirby stuff, 64 and Melee didn't have Knight or Rid', so when Brawl came around, putting in M'knight was the closest they could do for getting Rid' in there
I don't think them putting MK in had anything to do with Ridley. They've explained why they didn't want Ridley to be a playable fighter and they didn't once mention HAL or Kirby.
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Mewfii
This is what happens when you try to vote Ridley in for Smash...hey Smash is done by Hal Labs, not Retro Studios!