This is the correct answer and no other conclusions are valid outside of this. I really recommend anyone interested in the subject to read "Who we are and how we got here" by David Reich*. The book explains how mtDNA works and talks about our Neanderthal genes, among other very interesting things, i.e. how they have "found" ghost ancestors in our DNA, people/species that have to have existed but there are no findings of them yet.

*P.S. I myself got the book recommendation from a fellow Redditor in this sub, thank you!