This might be relevant…
My cat of Questionable Heritage is the most friendly animal anyone will ever meet. She has never met a stranger. There is a very rare visitor who does not wind up with a cat on his or her lap.
My step-mom is wonderful with animals, pet-sits for everyone and can approach the meanest junk-yard dogs anyone has ever seen. She can even "pet" bees. They won't sting her.
They met each other when Sumi was a kitten. Sumi took an instant dislike to my step-mom. To this day, when Mom comes to visit, Sumi hisses, whacks her on the leg and stalks out of the room. Sumi has never done this with anyone else in her life.
My point is, sometimes, animals take a disliking to someone for no apparent reason and there is no convincing the animal otherwise. It is not necessarily a reflection on either the person or the animal.
Perhaps this is the case here.
Like Forest Gump says " A Basenji is like a box of chocolates, you never know what you gonna get".