bayou / old zedicus;
You have to admit that the scenario proposed by QuickSeller (the account was sold with the intention to gain it back through signed messages) is at least plausible. If you got hacked/cheated I understand you're sour about it at best. But some restraint would be in order. Staying calm and reasonable is more likely to lead to an acceptable resolution. Rants filled with expletives are not furthering your case. Especially since even if you were hacked QuickSeller and the eventual account buyer may still have acted in good faith.
If I understand BadBear he has no conclusive evidence for either side, and thus no basis to act upon. In my society we are guilty until proven innocent. I extend that to QuickSeller / new zedicus.