i think he is stating that he touched the pos and neg cable together after disconnecting them from the battery. i'm not sure if this would be any different than just disconnecting the neg cable. the thought is that it completely discharges the car's electrical system.

has the OP verified that the relay control module is not faulty? Obviously that can cause a no crank situation. But it can also throw codes (like P0600 - data link failure). It can also result in a crank with no start. It might be helpful to know what codes the mechanic read.