You are responding to a post which is three years old. A lot has changed in that time.
Specifically, Alexa now has routines which allow you to do a lot of different things.
With regard to the specific post you are replying to, triggering from a custom voice response is just a built-in Alexa feature now. Here’s the information on it, contact Amazon support if you have any questions.
If you want to trigger it from a smartthings event without speaking to it, see the following FAQ: