Here’s another way to look at this without pulling these nodes out from the diagram. Below is a private miner who doesn’t want to be known, it has 8 random peers, and none of those peers knows that it’s a miner. Again, this is intensionally designed this way for privacy reasons. There’s no way for any node in the network to know that the block they received was created by their peer, or relayed by their peer. All they know is if it’s valid or not, and if it is they send it along, if it’s not, they don’t.