It is difficult to turn a group of lights on and off with an ActionTiles tile. This post from URTechTherapy provides a solution for switching a group of lights on and off.

1. Create SmartThings scenes for on and off
2. Create SmartThings Lighting Group with all lights
3. Create SmartThings Virtual Switch (add to “My Devices”)
4. Create SmartThings Smart Apps Automation for each Scene (on and off)
5. Create SmartThings Automations for on and off
6. Authorize Virtual Switch to ActionTiles and add to panel
   

Add Den LEDs On scene with action on for both devices
Add Den LEDS Off scene with action off for both devices
Add Den LEDS Group group with both devices
Create Den LEDs Virtual Switch in SmartThings
Add SmartApp/Smart Lighting/New Lighting Automation/Activate these scenes