I was at Century Mill Lumber at the right moment. They got in a load of Bubinga and only one board was like this. It sold for big money, and I got the live edge cut offs. (only $28!!!) The Lumber shop owner said he has never ever seen Spalted Bubinga, so I am thinking it is very rare.
Getting all the holes and defects filled for a smooth gloss finish while keeping the holey ratty effect was quite the process. Mostly used crazy glue/black paint mixture, and the traditional carpenter/sawdust technique, but mixing black paint into that as well.