I personally think the chance of disease or parasites that could affect a ball python from collected wood have been greatly overstated. It it's a concern of yours I would fill up a plastic garbage can with a weak water and bleach solution, weight down the wood so that it stays submerged and leave it to soak for a few days. Rinse very well and allow it to dry for a good long time. If it still smells like bleach, let it air out longer.