First, welcome to the forum. I will agree with your father that it is not a good idea to mix types of metals because of galvanic corrosion, but will not forecast how long it will last. It will vary depending on temperature, humidity, and if there is any current flowing thru the metal as in a ground system.
If it were mine, I'd redo the patches with aluminum sheet, which you can get from the same hardware store as aluminum valley tin.
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