Thought the same thing, co-worker of mine just thinks the 4th has his chakra. He also thinks that Naruto just cloaked everyone and didnt GIVE them chakra. The guy is a complete mess.
Well wait a minute. After thinking a bit on it, Your co-worker might be on to something. Since they both have half of Kurama inside of them, then neither are true Jinchuuriki (like Bee for example). Also, if I remember correctly, Naruto couldn't fully transform into Kurama like how Bee could turn into the 8-tails (he had that chakra form Kurama goin on). As for the whole cloaking thing, you co-worker might be wrong on that end.
I always thought that Minato died because a sacrifice was needed to make to jutsu happen. So Minato Sacrificed himself, because if Minato sealed half on the 9 tails into Naruto then the other half into himself who the hell did the grim reaper seal? Or for that natter why was he needed.
Also if he just has the 9 tails chakra why is the 9 tails speaking to him as if he were a Jink?
Has me wondering if Ginkaku & Kinkaku could do the same. (rubs chin)
That is the reason he died, he sealed it within himself because, as a whole, the nine tails was too powerful/big to be completely sealed in Naruto. He has the evil half, Naruto has the "good" half, as to why he's able to talk to him...guess its because he's been reunited with its other half?
As for the Gold & Sliver brothers, I doubt it because they just ate his flesh and gained some of his chakra