it’s a tricky one… and I get what you’re saying..
But what you are asking for is for FIFA to have intimate knowledge and private access to every bank account owned and operated by Man City and all their players.. and all before any inclination of any crime has been committed. From a Legal standpoint, I don’t know any club or player who would allow that.
and with regards to punishment, they may be expelled from the premier league but you can’t ’ expels them from football. One battle that Leicester City won was that a punishment dealt out in the premier league is not enforceable in the football league.. however, there is one caveat.. and that is if Man city get expelled from the prem, the football league are under no obligation to accept them into the championship. Or any division for that matter. And if they do, that’s going to have a knock on effect for everyone else- who is going to be denied a place in the champ at man city’s expense? Will the champ be able to operate with an extra team for a season?
however the Cynic in me tells me that the league will force Man city to hand over a large ‘ compensation package’ to whoever wins the first division play off for them to step aside for a season. Which will only reinforce the sentiment that money can buy you anything in football.