Amtrak is supposed to have priority over freight. That however does not mean that the track operators abide by that. The best thing you can do is contact our federal reps so they can give Amtrak a little teeth on the matter. I am sure that a fine paid to Amtrak for every minute that a train waits on a siding will fix the issue. It however is better now than it used to be.
Even the on board conductors were telling us Amtrak had to give way to the freight trains.