Occam's razor is for the obvious, it was a cross species jump of a disease from another animal (in this case a bat). Which happens somewhat regularly, and was already known to be a concern.
Maybe, but I somehow don't feel like their government would have fought to hide as much info about it unless they were embarrassed about something, so I feel like the razor cuts the other way. Can we really trust a government that hid things for so long? That said, I doubt we'll have any real proof one way or another.