Endangered species isn't the issue. Tourism is 80% of the economy of countries in that part of Africa. If you see how people there live you know that if you destroy tourism you have mass starvation. In countries like Kenya,Tanzania,Botswana,etc tourism equals survival.
People aren’t going to stop going to Africa just because the Rhinos no longer have horns nor the elephants have their tusks cut off.
Heck, at the current price they could sew back on fake tusks that the poachers would instantly recognize as plastic.