I have a 2010 Doblo Maxi van, but in fairness I am not looking at pulling panels off to inspect.
However looking at your two photos, assuming if the catch in the top photo actuates the lock and that bottom white clip moves when you work the mechanism I would try making up a link using a bit of 1/8th welding rod or similar bent to fit in the holes. The top one is probably just a hook shape through the hole and the bottom one an L shape that goes through the hole and the white plastic clip revolves around to clip into place. If you turn the white clip anticlockwise so that an L shape rod will drop through hole then as you turn the white clip clockwise again it should clip over the rod to hold in place.
A little trial and error bending the rod to suit should do the job.
Other than that it is a trip to the breakers or look on the parts screen at the Fiat Dealers to identify what to order.
The reason I suggest bending a rod to fit is, I have done this on front door locks in the past so know it is possible.