Im a ford tech in a main dealer, I have seen this bolt snap only once, that van had a new head and injectors as the injectors bouncing up and down smashed the mating surfaces, I have never heard of a repair kit, recall, tsb or fsa.
egr faults are very common, injectors go now an then, if your revs hunt at idle, or bob up and down then I would be looking at a pcm update. Now and then a dodgy imv valve will cause the fuel rail preasure release valve to operate, not likely for you as you have not complained of any other running faults
Timing chain faults seem a thing of the past now, not had one on the new puma engine, timng chain, tensioner and rockers are all different, tensioners failed more on old 2.4.