There is a separate board that is analyzing all of this anon's posts.
Yes, they probably did.
I don't think this Puchenko works for Rosatom.
The 2 Rosatom connections are this.
The original post before "over the target" pointed out Ivanov. It also included a link to a different person with a similar name that works at Rosatom.
There is an Ivanov who works at Rosatom but it is not the one on the plane.
So far as I know, neither person who works at Rosatom were on the plane.
This is the one with the name Ivanov who has the corresponding birthdate.