I have a couple pieces of driftwood and the bigger one(2'x1') stinks pretty bad when I take it out, both pieces have a lot of algae on them and there aren't any fin rot issues. But you are probably on the right track by at least pressure washing it and letting the sun cook it for a few months. May not be the cause but definitely couldn't hurt.
Sent from my iPhone using MonsterAquariaNetwork app
Sent from my iPhone using MonsterAquariaNetwork app