I came from a mfg background, and dealt with multi level BOM's.
A parent would be listed as level 1, children level 2.
Level 2 children could themselves be a parent, with a level 3 list of components.
From your description, you mention 6 levels, although ours varied and went deeper.
We were going from a mfg parent, and then blowing through to all the purchased components and qtys that it took to build any parent item.
I think what you are looking for is a CTE to make a distinct list of parents, and then chase down the hierarchy.
And then create more of an indented BOM look for the results.
Parent A
  Child A
  Child B
     Child 1 of B
    Child 2 of B
Your lists of results seem a bit confusing to me, as Parents are being repeated in what should be all the Child Items only.
So you may want to add a better example of what you really want to see in the end.
Especially where in my example, Child B is a Parent in it's own right, but also consumed as a sub assembly when Parent A is made.
Your requirements likely differ from ours, as we also could have a sub assembly qty of more than 1 per parent, so a bit of math might be in order.

Hope this helps.