I know that Pokerstars have their own Team Pros playing on their site, this does not prove in any way that the site is cheating, in fact many sites do employ Pro Players to promote the site on their "Twitch" and "Youtube" channels so the site can get more players to register and play against their favourite Streamers.
I have on occasions played against a British Streamer called "G J Reggie" in many Tournaments, Do I think that she is Cheating? NO! because she has many more los+-ses than she has Wins, She openly admits that she is far from being a top Professional but she is a Friendly Low stakes player and many of her fans enjoy Chatting and playing in some of her games.
I would never assume I am good enough to play against Streamers like Lex Veldhuis or Spraggy who play in much higher stake games than I do, but I do like to watch them play and learn from them.
Poker has many levels of Players, who have many levels of talent when it comes to playing the game, My task as an Amateur player is to determine my own level of play and stick to it until I feel competent enough to increase my stakes and play for higher stakes, just like a learner driver who has just past his/her driving test would or should not drive a big Muscle car or Sports car until they have had a few more years experience driving on the roads. Just like a Baby has to learn how to Crawl before they can Walk
So I would suggest that if you feel Cheated by any
poker site On-line, you should leave the site immediately taking your money elsewhere, or Learn to Walk before you can Run.
You know it makes sense!
When the fun Stops, STOP!