Hackles up are normal for a Basenji, I have never seen it make a difference, means nothing about a serious fight or not, IMO… usually it is the noise, or lack of it... My Kristii yells all the time at my boy...ggg.... and she always has her hackle up... and she is all noise, no action....
This is typical Basenji actions... when you have more then one... I have always told people get ready for the noise.. that you never had before.... sounds like they are going to kill each other... but they are not....
One thing that I can say is that if you ever see that "glazed" look in one or the other to where they are totally fixed on the other one.. that to me is a sure sign that something nasty is going to happen...