According to the shop Tesla says that warranty is ONLY if Tesla replaces the part.
Directly in this PDF I linked is:
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Exclusions This Tesla Parts, Body & Paint Limited Warranty does not cover: • Parts not purchased directly from Tesla; and, • Non-Tesla Parts including tires. Although Tesla does not require you to perform all maintenance, service or repairs at a Tesla Service Center or Tesla authorized repair facility, this Tesla Parts, Body and Paint Limited Warranty may be voided, or coverage may be excluded, due to lack of or improper maintenance, installation, service or repairs. Tesla Service Centers and Tesla authorized repair facilities have special training, expertise, tools and supplies with respect to Tesla Parts, Body and Paint repairs, and, in certain cases, may employ the only persons, or be the only facilities authorized or certified to work on Tesla Parts, Body and Paint. Tesla strongly recommends that you have all maintenance, service and repairs done at a Tesla Service Center or Tesla authorized repair facility in order to avoid voiding, or having coverage excluded under, this Tesla Parts, Body and Paint Limited Warranty.
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So, if your body shop is in fact "Tesla approved body shop" and also purchased the parts directly from Tesla, you should be good to go. If your body shop did not buy from tesla, thats an issue between you and your body shop, especially if you took it to them because they were tesla approved.