Formsatting visualisation title using report themes

I'm attempting to format visualisation titles using report themes - upon searching how to achieve this I came across this article:
https://ideas.powerbi.com/forums/265200-power-bi-ideas/suggestions/31543114-format-visualization-title-with-report-themes

This Idea is marked as completed with the link below provided:
https://powerbi.microsoft.com/en-us/blog/power-bi-desktop-july-2018-feature-summary/#theme

I have not been successful however in attempting to format the title of a stacked column chart visualisation.

Here is my JSON file, which successfully modifies my visualisation, just not the visualisation title as I had expected based on the above 2 articles:

{  
   "name":"Test",
   "dataColors":["#555555", "#444444", "#444445",  "#444446", "#444447", "#444448","#444449"],
   "background":"#888888",
   "foreground":"#999999",
   "tableAccent":"#AAAAAA",
   "visualStyles":{  
      "*":{  
         "*":{  
    "title": [{
                    "show": true,
                    "fontColor": { "solid": { "color": "#EEEEEE" } },
                    "background": { "solid": { "color": "#FFFFFF" } },
                    "alignment": "center",
                    "fontSize": 30,
                    "fontFamily": "Calibri, Cambria"
                }],
            "*":[{"fontSize":30,"fontFamily":"Calibri, Cambria","color":{"solid":{}}}]
             }
          },
      "*":{  
         "*":{
                  "grid":[
                             {  
                                "outlineColor":{"solid":{"color":"#777777"}},
                                "gridVertical":false,
                                "gridVerticalColor":{"solid":{"color":"#777777"}},
                                "gridHorizontal":false,
                                "gridHorizontalColor":{"solid":{"color":"#777777"}}
                             }
                         ],
                  "columnHeaders":[  
                                       {  
                                         "fontColor":{"solid":{"color":"#777777"}},
                                         "backColor":{"solid":{"color":"#FFFFFF"}},
                                         "fontFamily":"Calibri, Cambria"
                                               }
                                     ],
                  "values":[  
                                {  
                                  "backColorSecondary":{"solid":{"color":"#FFFFFF"}}
                                }
                           ]
                   }
                }
          ,"columnChart":{
      "*":{
       "legend":
        [{"fontSize":20}],
       "categoryAxis":
        [
         {"labelColor":
          {"solid":
           {"color":"#123456"}
          },
          "fontSize":20,
          "showAxisTitle":true,
          "titleFontSize":20
          }
        ],
       "valueAxis":
        [
         {
         "fontSize":20,
         "titleFontSize":30
         }
        ],
       "labels":
        [
         {"fontSize":20}
        ],
       "legend": 
        [
         {
          "show": true,
          "position": "Top",
          "showTitle": true,
          "titleText": "",
          "labelColor": { "solid": { "color": "#123456"}},
          "fontFamily": "Courier New",
          "fontSize": 30
         }
        ]
       }
      }
    }
}

Can anybody point out where I've gone wrong?

Here is a screenshot of my visualisation title: