> What that means, though, is not that other people haven’t proposed sources for dark energy, but this is the first observational paper where we’re not adding anything new to the universe as a source for dark energy: Black holes in Einstein’s theory of gravity are the dark energy.”

I beg to differ. This man has developed a theory of black holes without singularities called plugstars with a maximum gravitational redshift factor of 3, just like in OP article.

https://hal.science/hal-03835483/document

edit : the article talks about a k factor of 3, not sure whether it matches Petit's plugstar redshift factor of 3.