Sorry to hear about all these injuries, particularly those afflicting fellow Ponies.
MG - I don't want to dampen your spirits, but a mate of mine sustained a stress fracture of a bone in his foot doing the 3 Peaks last year, and it wasn't a quick recovery. I understand that 4-6 weeks immobilisation is usually necessary before a stress fracture of a metatarsal heals. It's not worth taking short cuts and finishing up being out for longer. Are you getting professional advice about what to do?
Anyway, bad luck and I hope it mends asap.