I suppose if the fridge was run un-level often or for long periods it could become damaged/blocked but hopefully it is not. If the heat sources are good (best to use electric to test long term since if the element works you are getting spec required heat; propane flame can get hot, but not necessarily hot enough to cool to spec) then the other thing would be a blocked roof vent.....or a side vent if the fridge is in a slide. Check for leaves or other obstructions in the venting system which draws air from the fridge access panel up through the upper vent. For such a new coach that is unlikely but you never know. One more link for you:
Troubleshooting a Defective Cooling Unit
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