Let's face it, Corbyn has got about as much chance of getting into power as my anus has of healing over...
As for him keeping wittering on about his mandate handed to him by his party, sorry, but with the simple expediency of joining the labour party for a couple of quid a lot of those votes could well have come from none Labour external forces simply out to cause mischief.
I would have accepted the vote if it had been open to current membership at the time it was cast, but it wasn't, so the doubt is there.