Nematode fossils 15 million years older than the Cambrian explosion?

https://www.science.org/content/article/mother-son-team-s-fossil-find-shows-how-nematodes-and-all-arthropods-arose
It looks like they have found nematode fossils in the same area that they are finding ediacaran fossils.  They think the fossils are in sediments 15 million years older than the Cambrian explosion diversification.
They think that they represent early members of ecdysozoans.  Nematodes are protostomes, but are more closely related to arthropods than other protostomes.  This would mean that animals like the phylum mollusca existed or at least branched off as multicellular animals long before their appearance and diversification during the Cambrian explosion.
Ron Okimoto