It was a mess. I'll take a crack at most likely scenario for you. The OP shows up trying to find this mule. Most likely she ran across the FB page for him and wanted the reward they were offering for information. She had no connection to said mule. She also posted the same stuff on other forums and got called out there too. In trying to find info to help the OP, before we found out she didn't know anything, we discovered that the mule had been taken from a barn over a year before it was reported. Again, most likely, the owners owed back board or something of the sort, and the mule was sold to cover those bills. After a year, the owners decided that enough time had passed that they could report the mule stolen, and get him back that way. They knew the mule had been at the trader's farm, but my guess (this is just a guess, mind you) is that they had to wait for the mule to be sold to someone before they could claim it stolen, because probably whoever sold the mule to the traders was the one owed money by the original owners. I'm sure they had hopes that whoever had bought the mule would hear about it, feel bad, and then give him back. There is no other reason to wait a year to report the mule stolen.
The person who claimed the mule had died was either someone looking to stir up a dead thread for kicks, or (again, just my GUESS, since this was their only post) is possibly the person in possession of the mule now OR maybe someone who knows where it is, and is sick of all the publicity about a stolen mule that wasn't really stolen. Can you imagine buying a horse and then being told it was stolen and how much they miss it and want it back, when it was never stolen to begin with, but sold to pay debts?
But it's really a moot point, since the OP and MuleGal have not been around for a while now.