If there is nothing obvious to indicate it has been "tampered" with, I doubt it. However, if there are some sort of special stickers or other indicators that had to be removed to gain access (never dealt with a mac), then they would realize it, and ask for proof it was done at an authorized center. But they wouldn't even have to ask you, because they would have records indicating if it was fixed at an authorized center, I would think, because they would have to reimburse the shop for parts and labor.
