I believe your problem is two-fold. First you allowed a patio cover company to do electrical work and second they hid it all behind one of the structural panels.
You will need to have the panel(s) removed to get at the source to the problem and you will need to get a real electrician out to professionally correct the problem.
Is the patio cover physically attached to the house? This might be your source of water infiltration and not the wiring hole and/or a combination of the two.
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