We didn't know that you have spent over 5K to hire people to get your rig started at your house. I can certainly feel for you.
Yes, it is an LMTV, but the engine is a 3116. A lot of school bus and RV use this engine. I don't see why a certified diesel mechanic can't handle it. If the engine cranks good and the fuel gets to the injectors, it will fire. The mechanic should be able to check items in question stey by step. It is not rocket science, but it takes time through process of elimination to sort this out.
I agree with others. When one commits t to buy an ex-military vehicle, he has agreed to get his hands dirty and be willing to spend hours on the internet sourcing out parts and tricks. If you are not in a position to do that, it is better to unload the vehicle and find something else. I don't want to sound harsh; it is the reality. It is not a reflection of a failure, it is just a little hiccup along the way. Walkout and be happy.
Good luck.