how rampant is cheating in CC

[Amarande]

I just started CC and I have seen 1 player take out an entire team solo. players go from no rank to gold in 1 hour

SAM LB will by design do exactly that if opponents are not aware of the mechanics.

As for the ranking thing, every game with ranking is that to some or other degree. Everyone starts out at the default rank regardless of their actual skill, and in most cases outside of advanced enough esports to actively feature a placement system (such as League) or online versions of traditional card and board games (e.g., Doman Mahjong here in XIV, or most online Chess servers), the starter rank is the very bottom of the ladder.

So if you're actually good and you play enough games in a short period, you should fairly quickly rise to near or close to your proper rating level, that is how rating is intended to work (although with CC it's a little weird because there are the ratchet points that you can't drop below once achieved, while in most games you can potentially fall all the way to the minimum rating on a bad enough streak).