First one:
If you want specifics:You missed it. You can get into the cage going left where the second bonfire is, before the bonfire.There's a gap in the railing on the right side before the amygdala shooting laser at you.
Second one:
I think the gatling gun hunter is friendly if you go that way, under certain conditions at least.
Not sure on the first part, but for this.If you haven't killed the Gatlin Gun npc, you can now approach him through the level unseen from behind. Make it up his tower and he is "friendly" and gives some stuff.
Ah OK, I'll look
Damn, a shame about that dude, I already killed him!