This is an hard situation.

So, let's try to sort it out.
I think that the best two options you have are:
1) stop the hand, give chips to the proper players and declare the hand dead.
2) try to reconstruct the board and go on with the hand. I stop at this cause I can't really, really really figure out how can you burn and turn the 4th and 5th street with a stub containing players' folded cards.
Is option 2 in the best interests and fairness of the game? I think not... but also option 1.
So definitively i think we should adopt the best of the two
I would adopt the first one.
#EDIT
oh, and by the way, fire the dealer lol
#EDIT2
I had a talk with 2 other TD's and we agree that this hand must be declared dead and chips returned back