The ground wire came off the bottom piece of the VAFC harness. (this part is gray and all 1 piece).

There is a small metal "stump" left of the connection on the grey piece, and the wire part has a small hole and what looks like the rest of the metal piece in the inside of that wire.

How can I repair this connection? You can take the wire and push it onto the stump (so one metal piece overlaps and touches the other, completing the connection) and it'll say for a few seconds, but then eventually pop off. I was thinking maybe superglue, since I have no idea what it would take to solder the wires back together since I don't have a solder gun or materials.

Advice or help?

The red circle is the "stump" and the blue is the wire that came off. FYI, it is the ground wire for both the ECU AND VAFC, since the two were wired together, so it MUST go back into that pin somehow.

sorry the pics are a bit blurry, my camera sucks.