Hi Kai,
I too have had escaping Basenjis. And usually it was the females. Have no idea why. They could scale the fence in a flash. One could even climb a tree with low branches. I thought this is really a cat - just looks like a Basenji.
So, how did I resolve the situation? Instead of the chain link or wooden fence, I installed a vinyl fence, split spaced slat design, 60" tall, with traditional vinyl full slat lockable gates. Something similar to the picture included here. This fence type was successful for two reasons: 1) the vinyl - to slippery - their paws can't gain traction, and; 2) the space in between the slats also prevents them from gaining any type of hold. At 5 feet they can't jump it! My fence had a wide slat followed by a narrow slat in an alternating style.
Two cautions (and these hold true for any fence and a slatted fence with a space between slats): 1) the bottom of the fence must be at ground level or just slightly above ground with pavers underneath if you have a digger or soft uneven ground, and; 2) the space between the slats should not be wider than 2.5". They may get a nose through but their head won't fit. Once this fence was in they just quit trying. Instead, they would run up and down the fence line or just stare through the slats or stick a nose through on occasion. Hope this helps.