Killer Bee is perfect Jinchuuriki, thus capable of replicating what his Bijuu can do.
Yes, which is why he goes full Hachibi to perform Bijuu Bomb.
What Bijuu can do is what Kurama did through Naruto in V2.
We have never seen the Hachibi perform a Bijuu Bomb through Bee while in V2. Neither has he implied that he can, or that Bee can. In fact, the very first step that they highlight for performing the Bijuu Bomb is to
You must be registered for see links
. Therefore I don't see why you're making this comparison.