Maybe you can drill a whole from the outside just enough to view the trace and the copper peg, solder it together through the whole and then close the hole up with a plastic patch and glue. It won’t be the prettiest fix, but soldering seems like a much better connection the this.

And this looks like a real engineers mistake to have such high current flow through such a flawed connection. Be safe though! Test a couple of times before trusting the machine again.