a wild guess: most likely it was a collected virus of natural origins in a bat cave brought to the wuhan institute of virology for research and/or potential weaponization, where gain of function research was being conducted. some lab technician or phd equivalent lab worker, inclusive of management did not follow glp (good laboratory practices) at the right bsl level (bio safety level) and accidentally leaked the virus to themselves/colleagues and then to the local population.
Norway