The answer is staring us in the face...
Katharina should set up an underpants folding company (a company that folds underpants).
Each player we sign also gets employed by the underpants folding company. The general public send in their disheveled underpants and each 'employee' spends 1 hour a year folding underpants for which they get paid £5million.
Given the underpants folding business has nothing to do with football, it is outside the governance of the FFP rules ergo we end up with players who are as wealthy as players at the 'big 6' clubs. They just happen to earn half their wages from a non-football industry.
And who hasn't got disheveled underpants? There's certainly a demand for this service out there. Its a win win for the players and the general public at large.