Well this isn't true. The PL have more than enough money to take on Man City. People forget that the PL is the world's 5th largest economies biggest soft power export. The PL is also playing this on home terf. Let's not pretend that the PL is some kind of pauper organisation.
As I have outlined on numerous occasions, the PL never had to bring this down on City as they had a 'get out of jail' card with the UEFA decision and owing to its' structure it doesn't have to disclose everything.
Thus, they must be serious and have a case they know that will win as otherwise they're going to look like complete clowns if City get away with it.
The question is really, what happens to City? My prediction is as follows:
1) City keep their trophies - PL won't want to dig too much into PL past standings as it could open a can of worms.
2) City will get a points deduction to essentially relegate them. Think 70 points+.
I do reckon they will avoid being thrown out. That will again be due to the PL wanting to protect the product as chucking them out will cause issues with fixtures.
At that point the real interesting bit will come into play, which is: do they EFL accept them?
My money is on yes, if not it is an extinction level event for City.