Had to go back to job today to collect dryer,
and to my suprise the carpet has gone virtually back to normal on its own all the rucking up seems to have flattened and were the carpet was about half inch of the doorbar its relaxed back and is now just touching it still needs to be stretched a bit and tucked back under but i think thats about it so hopefully should have no problems getting a fitter to sort it in the new year.
Even if it wont stretch its so close to the door i should be able get away with just fitting a slightly thicker door bar.
And i got paid

So lessons learned
Watch out for this type of fitting
always warn customers of dangers and let them know its up to them if they want to take the risk
and if the worse does happen give it a good few days to dry and relax back