They are not going to weld castings except maybe for very small cracks and even then it's very unlikely. The casting is not in a place that could be repaired i

They are not going to weld castings except maybe for very small cracks and even then it's very unlikely. The casting is not in a place that could be repaired if it were steel, though. It's the main structural member, located behind the rear seats. If you needed to weld there you'd need to take the car practically down to its frame. Even if it were in a place that was accessible and subject to repairable damage, you would not see it welded or cut. First off a lot of it isn't physically possible to weld; it's in very deep (6") pockets and you'd have a huge amount of difficulty getting penetration. Second, welding aluminum is not super easy. Anyone can weld steel, aluminum isn't the worst but it is much trickier. Third, aluminum welds create a weakness in the aluminum around the weld, because it gets hot but isn't properly tempered as it cools. It's still strong, but the loss is significant- temper is responsible for ~70% of the strength of common aluminum alloys. Fourth, the weld and the surrounding area are very weak (<40% strength) for several days after the repair. It's a huge pain in the ass and you probably can't just let somebody drive off on it.