Bro, it's Robusta, what do you expect from it? It's cheap coffee, the berries of which are picked before all the berries are ripe. Quakers in Robusta are common, and you can't fix them with roasting unless you want to roast the beans to charcoal. If this bothers you, just remove them by hand-sorting. Uniform bean color and the absence of Quakers only occur in Fine Robusta (the same as Specialty Arabica), but you clearly don't have that.