A supplement can look plant-based and still hide an animal-derived capsule....

https://www.booknose.win/plant-based-athletes-can-t-rely-on-the-front-of-the-bottle-this-article-shows

A supplement can look plant-based and still hide an animal-derived capsule. This article shows you how to spot gelatin versus HPMC, why “vegan” claims don’t have a federal definition in the U.S., and what third-party marks can—and can’t—tell you