ouch!!... hope he gets the hint.
sidewall damages are not repairable (not properly anyway). the best thing to do is to get new tires and, as you already have stated, park away from the curb. OEM tires generally do not get the miles that trade tires do (even if it is the same brand and pattern). with 35K miles, you should be about ready for new tires anyway.
the question you ask is similar to "which came first, the chicken or the egg".... it's difficult to tell whether the sidewall puncture resulted in the flat, or you running it flat caused the puncture to open up. anytime you have a significant cut, puncture, etc., you add stress risers to that particular area. add to this the deflection when the tire rotates with 1000lb of load on it, or when you hit a pothole, etc.... the situation doesn't get any better.
it really is amazing what tires go through and how they hold up. afterall, they're the only contact you have with the road.... 4 small areas on each corner of your car. so you really should look into new tires. (sorry for rambling)