SharePoint Framework Extension for a list

I think you should check for your desired site and list inside 

@override 
public onListViewUpdated(event: IListViewCommandSetListViewUpdatedParameters): void {
let desiredSiteList: boolean = false;  
const compareOneCommand: Command = this.tryGetCommand('COMMAND_1');
    if (compareOneCommand) {
      // Check for site title/url and list here and update desiredSiteList
      compareOneCommand.visible = desiredSiteList;
    }
  }