The price in the covenant is from before his time.The question is in the definition of 'realistic asking price'. Presumably the council sold it to the golf club at a realistic price for a golf club. What is the realistic price for a football training ground? Or is Soulsby trying to 'screw rich foreigners'. I'm sure that people living closer than I do will have an opinion on that.
Clearly the current owner of the golf course knew of this, perhaps he chose not to divulge in the early stages and though once the club had plans they'd pay anyway?