The article mostly describes how elephants populations have been dwindling with the ban in place. I do not see any statistics supporting the view that elephant populations will dwindle any more quickly/slowly without a ban.
http://www.iol.co.za/dailynews/opinion/controversial-call-fo...
"About half the continental population was lost in the decade before the Appendix I listing in 1989, and a dramatic spike occurred again after a “one-off” ivory sale in 2008 to China and Japan."
"Cites [Appendix I] saved African elephants from certain extinction 27 years ago by listing them on Appendix I. It ended the poaching crisis and elephant populations began to recover, until their protection under Cites was weakened, causing poaching to escalate again."
It was not exactly the lift of the ban, it was that Western nations decided that the problem was controlled, or that it was time that African nation started taking care of the poaching problem themselves and cut funding.