no right or wrong answer to that question, IMO. What didn't work this time very well may work next time. But over the years I've had vocal responses and used more howls to call them in, but I've also switched to rabbit of some flavor and had it work too. And I've had times where they did exactly what they did to you. We had a coyote yesterday that I spotted after we had been calling for 10 minutes that was 1000 yards out, and he would stop and listen with each sound we made, but it eventually just wondered off without a care in the world.
If and when someone figures out how to make them come every time they can hear a call, they will be a rich man.
With all that said, this time of year rabbit should be the primary successful sound, and with the cold weather finally coming in, their drive to find food should only get stronger. This warm weather has been making it easy for them to survive without running too every dying rabbit that they hear.