You paid for a diagnoses.
not only did they fail to give you a proper diagnoses, they also failed to give you any information about what diagnostic work was done.
You say you've got fuel in the rail, have you pressure tested it?
I will call them and ask how did they come up with the distributor as the issue...only thing Im sure theyre gonna say is being that I was the one who installed it, they would have to look at it again. Im not going back to them.