And that is why I made the suggestion of flipping tip and ring where they are connected to the network.

It's entirely possible that the contacts are dirty on the back of the dial. I've had to clean more than a few to get them working.

I knew the spades were going to be attached to those plastic strips, which is why I thought of flipping t&r at the network if it's only this phone. Maybe someone flipped them before, who knows. These things are all pushing 40+ years old. There's no telling who's been in there poking around. My advice is get the BSP, make sure everything is wired as it should be, if not, correct it, then move on to cleaning the dial contacts. No sense in beating your head against a wall if someone has changed a bunch of wires around. Make sure it's wired like it just left the factory, then start the real troubleshooting.