There are serious problems with testing a potential remedy too early:
1. It can cause actual harm to the patient (e.g. organ damage, etc.) - the cure might be worse than the disease.
2. If tried too early, the illness can begin to build up a resistance to the drug (i.e. mutate) before it's widely available. This means that when it's finally in general distribution, it won't be as effective.
3. Further down the line, one has to worry about interaction with other drugs. All too often, a drug that works fine on its own can be highly dangerous if the patient is also taking other drugs.
Doctors have to worry about all these things. Sure, as a patient, I'd want to grasp at any straw available if it would help an otherwise helpless situation: but the doctor has to think about more than just me... which may suck for me, but may save a lot of lives further down the road.
As for this particular outbreak, yes, Angola (and Zaire, and other nations with widespread disruption caused by civil conflict) is a very good place for it to develop. There are minimal medical and social services, widespread social disruption, a low level of education (and a correspondingly high level of superstition and fear of the unknown), and all the other factors that lend themselves to an epidemic. The WHO has its hands full on this one, and I understand several medical personnel have already died from the disease.