Vulcanizing the tire sidewall can result in "bukol" coming out due to the sidewall's lessened strength. Even if a bukol does no come out, its not advisable to repair the tire for daily use if that has happened.

That (sidewall damage) happened to our cars twice already (dinamay ng driver namin) and it really hurts your wallet, especially when the tires are still new as was the case with ours. However, safety comes first so its better to put another tire and use the sidewall damaged tire as a spare at the least.

My .002