I'd do more or less what you plan, except I'd get one of those small epoxy syringes that mix the hardener and resin in the syringe and the mixed product comes out the end. JB Weld would be good but it would be hard to force it into the hole. Just fill the hole with epoxy and then screw in a stainless larger screw. Be careful about how large you go since it's easy to wring the head off or strip the threads on stainless.
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