I think in principle the rough figures presented are sound. So they got a net three months operating costs in a grab back (approx) and then some kind of rolling income for ever more from donations. Up front investment and operating costs on Temple Farm must be pretty large. Looking at the amount they send overseas it does not actually look like they have a load of cash to spend on TF and they cannot realise the assets in Mill Hill as they need them.
What better plan than to chuck 50% of the family out now and sell the properties early to keep the build rolling.
If the same is true in the US then the cash may really and truly not be there to splash. Don't forget as well that there is a big development in SA as well and they cannot support the build locally, they need outside financial help.
As slidin' says, it needs much more of an expert eye.