I would be very surprised if they haven't broken any rules, if the allegations are true. There are basically two ways situations like this can happen:
- Two clubs are genuinly interested in players from the other club, come to an agreement both ways, and then inflate the fees.
- Two clubs conspire to find some players to exchange so that they can inflate fees.
In both scenarios, there needs to be a "real" valuation at the bottom of it, which would be the transfer fees they'd agree on without any tricks. This is pretty obvious, because the difference in valuation between the two players decides the difference between the fake fees as well (it can be more that two players, of course, like the Oshimen deal for cash + 3 overvalued players). So, if two clubs exchange players they agree are worth 5m and 7m, then when they inflate the fees they can go e.g. 10m and 12m, 15m and 17m, or - theoretically - 105m and 107m. Or, if it's just one of the clubs that really needs this, while the other isn't that bothered, then they can do it skewed as compensation. Like, for instance, 15m and 19m. 10m inflation, and then 2m on top for agreeing to participate. Whichever way you slice it, you need to have an idea of what you actually value the players at to arrive at an inflated price that makes sense. Overvaluing assets like this, because it benefits you in some way, is fraud. I would be astounded if the PL doesn't already have rules against fraud. It's also likely criminal, because these inflated fees don't just go in a PSR report. They go in the accounts you have to give to the government.