Assuming what you say is true, what happened? All the accounts we are getting say that the Iraqi troops left behind their weapons and uniforms and joined those fleeing the area. ISIS knew exactly where all of that money was and it was not protected? It does not sound like the soldiers in that part of Iraq had the same priorities as the governments that pay them.
And why is the US still trying to topple Assad? The only way to stop these maniacs is with governments in the area that still have strong leaders that have not been compromised or hand-picked by the US.