Very Sick Pawpaw

Lex starts with ...
We recently purchased a dozen or so fruit trees from Daleys - and they all arrived in outstanding condition.
We followed the planting instructions and tended the trees each day.
For Mothers' Day we went away for a long weekend.
When we arrived back all the trees looked fine except for the Pawpaw which looked very sick indeed.
As the soil on the surface was still moist and there had been no frosts I've concluded that it must have got wet feet - but it seemed to sicken very rapidly for that.
Anyway, I have carefully removed it from its hole (along with a good lump of soil) and repotted it.
I've also located it alongside a western facing wall to keep it warm during the night.
Is my diagnosis correct or is there something else that causes a Pawpaw to deteriorate quickly.
Any suggestions as to how we can revive it will be most gratefully received.
Thanks
Lex

Pictures - Click to enlarge
Picture: 1

Andrew says...
Hi Lex,

That paw paw looks very sick indeed-from looking at your picture i would assume that it has or is suffering some sort of stress be it water or fertilizer.Did you fertilize the area where you planted recently??I would suggest from my experience planting in a potting mix (if you want to try and salvage it) with no fertilizer and use a fish emulsion type feed to try and get it on its way again, that's where i would start.It does look very sick so maybe after the feed bring somewhere nice and warm and keep an eye on him.