The worst thing I think I can say about this guy with my undergrad-level physics knowledge is that he's a self-promoter, to a degree that's kind of distasteful in pure science. But the idea is at least cute.
I don't immediately get how it's proposed that the two universes couple, though -- from the reference to dark energy and repulsion, I figured that it was a sort of gravitational repulsion, but then there are references to eliminating the need for dark matter, which provides a missing _attractive_ force. So I'd like to know a bit more.
But a very big red flag is that the cites 17-38 are a mix of preprints, arxiv's submissions and conference proceedings, where one of the authors is the site owner. The last article published in a peer review journal is from 1995. This is not usual in physics and cosmology.