Well I disagree that there are legit uses for e-collars even in hunting. Since other countries and most trainers here can train without them effectively, it's an unnecessary tool. Any trainer suggesting one for anything other than life-endangering issues (going after snakes and bees, rock eating, for example) isn't one I'd use. Period.
To the OP… well, dog aggression is normal. It really is in many breeds and many dogs. Instead of making your dog LIKE other dogs, why not simply and easily MANAGE it? Get a basket muzzle for walks or vet visits, etc. Your dog will never bite another dog. Ask people to keep their dogs away from your dog. Dogs are not little children who must learn to play with other kids. Your dog can have a full and happy life never interacting with another pet outside of your home.
Many basenji also are wary of strangers. You can work on that easily... go to a park with a helper. Have the helper give out treats. At first have strangers just pass by and toss one to him, not approaching. Have them slowly get closer. After a few times, have them come up to him and drop the treat, still not touching, for a few visits. Next, have them actually hold a hand out to give the treat in the palm of their hand. It won't take your dog long to associate strangers with GOOD. But a lot of dogs do not want several people at once, or anyone moving fast. In your home, crate him til visitors are in and seated, then let him make all the contact. Again, a small treat will help sooth the path so he comes to think visitors equal food/good.
We can control our dogs, we can limit bad responses by limiting the things that cause issues, we can train for many things but you cannot untrain animal-to-animal aggression. Only impressively uninformed people believe that it is ALL in how you train them. People like that get pit bulls and other dog/animal aggressive pets and end up with family and neighbor pets killed because they fail to grasp that there are genetic factors at work. I hosted on an APB board and rarely did a month, usually a week, pass when someone wasn't on there crying their pit killed the family cat/dog etc and how SHOCKED they were because the dog was 2 or 4 or even older and SUDDENLY "turned." No, they didn't "turn" they matured. Not all APB are animal aggressive, but enough are (and they are BRED FOR IT!) that only owners who acknowledge it, understand it and are ever vigilant for signs avoid tragedies. And while Basenji are not as animal aggressive in general as APB, you had better believe and understand it is NORMAL in the breed. Talk to 1000 owners and you'll find most who have or have owned a basenji that would fight at the drop of a hat with strange dogs and/or their own house mates. You will find massive amts who cannot let their OWN DOGS, who grew up together, out without a fight and must keep them separated. We don't euthanize (which is what will happen to your dog if you "return" it to the shelter and are honest about the dog aggression) them over their nature. We manage and control it so it isn't an issue.
And back to shock collars... sure they can work. I darn well guarantee you if I put one on my child I could make her clean her room. Does that mean that it is good, should be used, okay? No. Again, many countries have banned them and oh my gawd their dogs are still being trained, doing great. Clicker folks have proven research after research that you can do more better with a clicker than any shock collar. It is the need for fast and easy, not better, that leads people to them. In dire situations, we sometimes grasp for such things... myself included. But they are not "training tools" but desperation ones, rarely justified. And I'll be glad when we join other countries and ban them.
http://www.goodnewsforpets.com/Articles.asp?ID=147
Consensus of Veterinary Behaviorists: Never use a shock collar "Never, under any circumstances, choose a dog trainer who uses an electronic collar (shock collar)."
http://www.patriciamcconnell.com/theotherendoftheleash/simply-wrong
Patricia McConnell: Simply Wrong
A PhD dog behavior expert explains in lay terms what can and does go wrong with devices that shock dogs
http://petprofessionalguild.com/shockcollars
Pet Professional Guild Position Statement on the Use of Shock Collars in Animal Training
This document both explains in very clear language the problems with shock collar training, and includes scholarly references.
http://www.dogdaysnw.com/doc/overall_collars.pdf
Considerations for Shock and 'Training' Collars" Statement by eminent veterinary behaviorist Dr. Karen Overall about the use of shock collars.
http://www.rottilounge.de/downloads/E_collar_Article.pdf
Clinical Signs Caused by the Use of Electric Training Collars on Dogs in Everyday Life Situations Research paper published in 2007. Conclusion: "We recommend that the use of these devices should be restricted with proof of theoretical and practical qualification required and then the use of these devices should only be allowed in strictly specified situations."
http://www.humanespot.org/content/training-dogs-help-shock-collar-short-and-long-term-behavioural-effects
Training dogs with help of the shock collar: short and long term behavioural effects Research paper published in 2004. Conclusion: "The conclusions, therefore are, that being trained is stressful, that receiving shocks is a painful experience to dogs, and that the S-dogs (dogs who were shocked) evidently have learned that the presence of their owner (or his commands) announces reception of shocks, even outside of the normal training context. This suggests that the welfare of these shocked dogs is at stake, at least in the presence of their owner."