ok so theres nothing i can do at home that proves anything. what do i actually ask a seller then

Batch number, date and place of collection, who tested it and when, and whether that document matches the jar in your hand. If any of those turns into a story instead of an answer, you have your answer.

honestly its the paper trail and whether they flinch when you ask for it. rest is vibes. annoying but thats where we are