It's not a coincidence. Heroin is an intravenous drug. Do you know how expensive sanitary needles are? Junkies wasn't hitting up the pharmacy to get clean needles before every hit. Sharing needles and reusing needles...that's a great way to get a plethora of viruses. Hep C, Hep B, and ESPECIALLY HIV.
Now sure, I can't rule out that AIDS was man made, and maybe the man did want to test it, but who really knows. All we can do now is spread awareness and educate. It isn't going anywhere anytime soon. One thing I will say also is humans aren't that smart yet. We can't just make out viruses. The HIV virus is very similar to other viruses that occur in monkeys and other mammalian species have their own "versions" of HIV if you will. Monkeys especially are in close proximity with humans...you don't have to fukk one to get a virus to mutate and cross over. Look at Ebola as an example.