Broken Bolt

Hi, I have been getting advice from here on this car due to seriously melted wires from the starter to the battery with the last time causing a dip like hole burning in my EGR valve pipe and all of this resulting in a no start. After changing numerous sensors and there harnesses my plugs and wires all the wires from my alternator and starter to my battery and at that point still nothing. So I have now replaced all my relay fuses as well and checked all wiring for issues and fixed the ones I have found. However, here is my newest issue. There is a bolt that screws in the car's wiring harness to the computer it has broken in two with one part stuck inside the computer and the other in the harness. I have bought screw extractors and tried drilling it out on both ends and can't. I have thought of soldering or even gluing them back together, but don't know if it is safe or will even work. Do you have any suggestions?