Timeshare Scam?

My Father-in-Law recently was contacted by phone by a company called Diamond Consulting Ltd. from Basildon. They claim to be acting on behalf of the Spanish Court in relation to a case against a company called Incentive Leisure Group who have allegedly been ordered to pay compensation to timeshare owners for a scam involving the reselling of timeshares and replacing it with holiday club ownership. You've guessed it, Diamond want £995 up front to be deposited in a Nat West Bank account in return for the payment to be released (in this case £14,400). Initial reaction is of course that this is a scam, but enquiries with Companies House and long conversations with both the initial caller and a manager at Diamond have got me wondering if it may be genuine. I can find nothing on line about the company except Companies House stuff and nothing on any forums.
Anyone got any knowledge?
I am awaiting a written offer from Diamond before considering my [well, my Father-in-Law's] next course of action.