No, If I have the custom payload as the only response, nothing visibly happens. I added the simple response as a second (below the c.p.), to see if the intent is triggered, which it is.
I’m using the ES Console. Afik you cannot specify the channel in the response message: you add a channel by clicking the +, which causes an extra tab to appear for that channel. You then enter the responses specific for that channel on the tab (see screenshot for reference).
However, I experimented a bit with the Custom Payload by changing “simpleResponse” to “hangouts” and “chat”. In both cases this causes an error message in the Chat: ‘Bot isn’t responding’. Still, I don’t know how to solve this issue.