If you want to get that Muller maul, I would not depend on them making contact with you before the next order goes in. Place the order with them now, or soon.
As regards splitting the oak, remember what was said earlier. Attack the round first from the outside, where the rings are at their widest. Going down the middle, only makes hard work harder. Out of curiosity, how did you 'finish' with the 8lbs. sledge hammer? I would have thought that once the round was opened up, it would be relatively easy to continue with the maul.