You all lost me back at post #68. If the pressure sensor is at all an issue, it should be tested right at the connector for the three wires going into it. If two or three folks compare what their readings are without any brake pressure and with a firm depression of the pedal, I would think we could tell if there was enough of a difference to be an issue. The measurement should be taken with the car running and the trailing wire (of the three) identified. The reading would be from this wire to ground and done by using a "piercing" probe on the VOM set for VDC.
Beyond that, I am lost. I do not follow what you are trying to read at the module pins themselves. I can only speak from my personal experience, but I found ATE1234 (Auto & Truck Electronics) on Ebay to be a very good value as a re-builder of modules. Don's (the pres. of ATE) price of $105 for a rebuild with a lifetime guarantee is the least I have seen and he tests every module before rebuilding to see the "as-received" condition. He is even good about letting you speak with the tech. that works on your module after-the-fact if you would like to know what they found once they split your module open.
Beyond this I can't help you guys. I applaud the spirit of taking a thorough and logical approach such as you have been. It just seems at some point you lack the data you need to go much farther and that is where an ATE comes in. G/L