Hi Tony,
I was running into this same issue with SetMenuPanel(), and it was this thread that let me to the solution: Conversation Trigger needed "Conversation Actor" to be set to a gameobject with the same name as the actor specified in SetMenuPanel(), in order for the response panel to correctly change.
However, from what I've read in change logs, this behavior was supposedly changed in 2.2.4 so that the gameobject was no longer required. I'm currently using 2.2.7, have I encountered a regression? (Or have I managed to incorrectly update DS to the latest version?)
Relatedly: Would you consider altering the behavior for SetPanel() and SetMenuPanel(), so that the actor is an optional variable? (eg: SetMenuPanel(1) would make the second response panel appear for everyone, until either the command is used again or the conversation itself ends.)