1999 Ford Expedition Fuel Contamination

My automotive question is in reference to a fuel contamination/vandalism that occurred to my 1999 Ford Expedition which has approximately 200K miles. It has been discovered that my vehicle was maliciously vandalized with a foreign substance (muddy-like & gritty) that was poured in the fuel tank. I was not aware that any tampering of my vehicle had taken place, hence I attempted to operate the vehicle and then later discovered that the fuel system had been contaminated. I had the vehicle towed to a local repair shop which was referred to me by a friend. After the vehicle was taken to the shop for repair it was discovered that there was indeed a foreign substance that had been placed inside of the gas tank and needed repair.
The automotive repair shop advised me that the following parts needed to be replaced or cleaned to correct the problem. I was advised that the gas tank needs to be flushed, the fuel rails needs to be replaced, the fuel filter needs to be replaced, the fuel pump needs to be replaced, the fuel injectors needs to be replaced and all seals/O-rings needed to be replaced.
My insurance appraiser states that all of the above needs to be done with the exception of replacing the fuel injectors. With a vehicle with this high mileage should the fuel injectors be cleaned & flushed or should they be replaced?
Also I would like to know if the fuel contamination problem can cause other mechanical related issues or problems?