Rossy got mad pissed at moose for doing so shit that he asked for a replacement (possibly victor as he's a free sentinel rn and also ight rn or someone else). C9 probably considered his ideas but either Victor asked for too much and they couldn't afford him or Immi didn't want to drop moose for some reason. Whatever happened I imagine rossy just got mad pissed that his opinion as an IGL wasn't considered and a massive fight broke out, because of that C9 thought it would be better to just drop rossy as they didn't want to deal with him anymore.
Just some random theory that I came up with and in no way is it right or anything just my ideas.
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