Seriously though, does a rhino horn have any circulatory connection to the rhino?
Because if not, something to consider would be injecting some sort of incredibly toxic poison that cannot be detected. Then if it's ever consumed, the person consuming it dies or is made incredibly sick.
Then poachers won't know which rhinos have been tainted, so all horns will be suspect and people purchasing them will stop.
As a woodworker I can guarantee you it's fake because wood doesn't break like that.