if its to large to boil poor boiling water on it in your bathtub this should do just fine honestly, then soak if you dont want "dark water" if you want amazon dark water just toss it in the tank. if it doesnt sink, attach a peice of slate to it with predrilled holes and deck screws if it sinks well then you are good to go.
When I bought my driftwood, I put it in hot water and let it sit there for an hour or so. When I came back the water was all brown so I drained it an repeat. I did this until the water stayed clear, then I added it to my aquarium. Nothing bad happened and the water stayed clean and my plecostomus loves it