Remove the dot from assignment. (admin hook)
Remove also the undefined variable (dashboard index)
             'memberInfoRecords'  => $memberInfoRecords,
             'clickThroughCounts' => $clickThroughCounts,
             'detailViewCounts'   => $detailViewCounts,
-            'thisDate'           => $thisDate,
         );
 
         // Return status, suggested view, and data to controller.
 
 add_filter(
     'glm-member-db-dashboard-member-widgets',
     function ( $member = null ) {
-        $content .= $this->controller( 'dashboard', 'index', $member );
+        $content = $this->controller( 'dashboard', 'index', $member );
         return $content;
     },
     10,