I await correction, of course, but, I think the £2.4M, offered by Prince Harry to repay the cost of the house refurbishment, is a bit of a red herring. My understanding is that those costs came from funds specifically put aside to keep these properties in good repair. The Prince of Wales, I believe, shelled out for fittings and fixtures so, that is a private arrangement between father and son.
All the other things agreed for their future are still to be seen. Let us wait and see what happens next.