I'd use the rotor as is, you are correct the lug bolts hold everything together. If you decide to replace the rotor you should replace both sides, they are only sold in a set anyhow.
Oh yes. you didn't warp the rotors while pounding on them I hope? Oh, take that back, I think you're replacing the rotors in which case it won't matter if they got bent.
Incidentally the rear pads tend to make noise more than fronts, so a liberal application of grease to the pads is necessary esp with other than OE pads

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