hard brake pedal cant get back brakes to bleed.

I did not see anything about the wheel cylinders being replaced, do you have disc brakes in the rear? I have had brand new wheel cylinders not want to work until I said the correct combination of swear words, then poof they worked.

I would start at the rear brake hose. That has been a source of issues for me. Disconnect it at the tee on the rear end. Have someone or yourself press the brake. If fluid comes out then you are good at that point. If nothing comes out take it completely out , have some one press the pedal again and see if anything comes out of the steel line that goes to the rear brake hose. If the master cylinder is working you will get fluid hear. Also you can pour some fluid into the rear brake hose, since its off , and see if there is an obstruction, or just look through it.Then depending on how long the car has sat the wheel cylinders may be stuck or the tee on the rear end is plugged. I would then disconnect at a wheel cylinder and press the brake pedal and see if any fluid is expelled from the brake line. Either way its all trouble shoot at this point , but you will have no choice but to crack open the rear brake lines.