Well, according to that growth process, it would be just a fungus. It would not have a parasitic relationship w/ a mineral (vermiculite), as it would w/ a worm/insect. In that case, it would be vegetarian friendly, and according to the definition of a vegan (It's only animal tissue and byproducts that are avoided), should be friendly to them to.
Thanks for the info dirk!
Let me know if you think there are any other concerns w/ it that would make it not vegetarian (such as using insect parts/residue in the vermiculite, etc). Would the artificially cultured cordyceps have any remnants of living organism in it from insects or anything else?