Your refutation does not address the article.
As usual trying to put the burden of proof on the other person. It is up to you to show that life can continue to exist for hundreds of millions of years under ice. It cannot. Life needs sunlight to produce the food which all life needs. And do not talk to me about chemosynthesis, because the life that existed before the Cambrian was photosynthetic bacteria.
There are whole ecosystems in the deep sea vents of the world's oceans now that don't depend upon photosynthesis, that live in total darkness, and that don't know or care whether the top of the ocean is frozen over. Also, some of the most extremophile life forms on earth are thought to be some of the earliest-appearing, the Archaea.