Not sure what you mean by left overnight with AC on and temps went up. The inside temp of the fridge got worse? Or better?
High ambient temp is hard on an absorption fridge. Propane is the most efficient method followed by AC then DC in my experience.
Lack of airflow through the vents outside the fridge will decrease its efficiency as well. And stuffing it completely full of food that is half cold will take it a loooong time to cool in high ambient temps.
Rv fridges need babied a bit when it comes to these types of considerations.
Wife packed ours FULL of groceries prior to this year's trip, including a bunch of warm cans. Plus added a bunch of food not yet frozen to a packed freezer as well. Fridge wasn't worth a c rap for almost 2 days. Guess she forgot what I told her before shopping. ("Honey, yes we are going camping for 3 weeks, but we are not in Alaska. There are grocery stores, so only shop for 4-5 days, ok?")
If your door seals are good and it otherwise works well you likely just were on food overload combined with high temps.
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