Yes, the digging is really the primary cause of the destruction. He only does this when he's about to take a nap. I will say that, so far, the leather couch hasn't been subject to any digging. I only see Kananga behave this way around "soft" surfaces, such as fabrics/carpet/bedsheets. The last couch was microfiber and was also a sectional. He would always do this in the corner of the sectional.
He still digs into carpet and other soft surfaces, but he has yet to show this behavior on the new couch. I'm not sure if they ever outgrow this, all you can really do is adapt (just like everything else with Basenjis ).
So I have a feeling that not only will the leather hold up to any said abuse, but he will be less likely to even attempt to dig. Time will tell.