The former is correct, the latter isn't. He strictly opposed German colonialism, quite polemically even, and only gave up his resistance when German entrepreneurs had already made it a fact. He didn't do that for any racially benevolent motives, obviously, but it's hard to blame him for the genocide on the Herero and Nama when it happened after he died and he never wanted Germany to be there in the first place.
To be clear, I don't hold the views I expressed earlier in this thread anymore, I'm certainly not a Bismarck fan, and I'm not saying he wasn't a racist, but we can't over simplify things this way. Colonial agitation and racist motivation came from far deeper within German society and was much more complex.