Recently, someone shared a possible solution to the Soft-Tissue Challenges for millions-of-years models. (https://www.earthmagazine.org/article/dinosaur-soft-tissues-preserved-polymers)
I see the advancements there for trying to preserve these chemicals for millions of years, but as I did a little more research, there still seem to be reasons to be skeptical (as we ought to be as scientists, right?!). Definitely a topic that we will need to keep studying!
I especially like the part about the worm in this article: