Hypothetical "Nemesis the bringer of destruction"

Hypothetical "Nemesis the bringer of destruction"

Sometimes astronomers are looking at the Planet Nine or Planet X(1) or "Nemesis-star"(2), what they expect to be found in Kuiper belt. The idea of those missing planet or star has been formed, when the astronomers noticed the strange errors between calculations and metering of the trajectory of Neptune. And the similar errors in the trajectory of Uranus caused that astronomers started to look for Neptune. 

On Planet Nine and "Nemesis" star is conducted many legends and one is that some dictators like Adolph Hitler have tried to escape to the solar system of that hypothetical star. There is no proof about this kind of plan, but that kind of thing always interests the novelists. But the reality is that nobody ever has seen the Planet Nine or "Nemesis-star". So that object is the purely hypothetical thing, what is mentioned being some Brown Dwarf or super-earth. 

The legend of this strange and still hypothetical red or brown dwarf star, what orbits the sun, or what would come so close to our solar system, that it causes terrible disasters on Earth has been somehow quite unknown for the great audience. There has been introduced the idea that "Nemesis" would be Proxima Centauri or Luhman-16 and Barnard's star, which is coming near our solar system in a certain period. 

The thing is that it requires that Barnard's star Luhman 16 are also orbiting Alpha Centauri, as well Proxima Centauri does. In image two is the diagram of the nearest stars of our sun, and if we would want to search Nemesis, we must think about the Alpha Centauri as the middle point of the diagram. 

And Alpha Centauri double star is more massive than the Sun, and that means that this object has a greater effect on its neighbors than the sun. But the thing is that the trajectories of those stars don't match and there has been introduced that the mysterious "Nemesis" is the phenomenon, where those stars are in the line, and that causes a powerful gravitational effect in our solar system. 

But the question is, why nobody sees that star? The problem with Nemesis is connected to the problem of hypothetical "Planet Nine". Where is the ninth planet of our solar system? There could be one answer for that thing, and that is that the star, what had rendezvous with the Sun has been "stolen" that planet. And is that star "Nemesis"? If "Nemesis" exists, what of those stars it could be? 

Or is "Nemesis" some kind of black hole (3) or "silent" neutron star, which travels in the empty area in the Universe, where it has no contact with the material. And that means there would be no radiation either from a black hole or neutron star. 

(1) https://en.wikipedia.org/wiki/Planet_Nine

(2)https://en.wikipedia.org/wiki/Nemesis_(hypothetical_star)

(3)https://www.livescience.com/tiny-ancient-black-hole-planet-nine.html

Image: https://upload.wikimedia.org/wikipedia/fi/thumb/f/f3/Proxima_B.png/800px-Proxima_B.png