Based on the information above, GLA and EDI would probably have a case against PIK/The Scottish Government for distorting the market by the use of illegal state aid but I can't imagine either would want to bring such a case as they would probably have to then reveal the deals they do with airlines and would it really be worth it to p off Ryanair and the Scottish Government (or at least the SNP).
the current prices Ryanair are paying would probably have been agreed before the government took ownership of PIK. They will need to wait until the current deal expires before it can be re-negotiated.