What you have is very normal.
Another thing that's normal is for RV manufacturers to ignore the installation instructions in ragards to clearances and flue baffling.
It would behoove you to pull the fridge and follow the install instructions to the letter.
Also, I would create a radiused or angled flue to smooth the flow of air out the upper vent rather than the hard 90 degree it probably has to make now.
If you can provide the chimney effect the manufacturer instructions describe and smooth the flow of air exiting the compartment, it will cool better.