Hopefully they did not fry foods in the RV or some crazy thing. Oily surfaces can Make the paint fish eye from the oily film is possible, probably more so likely with Spraying as opposed to rolling the material on. It happened to me when I was spray painting a used Kitchen cabinet once as I did not prep / Clean super well before slapping some paint on it.
I love using "Flood" (Orange label) Brand Paint additives to mix with any baseboards or Cabinet paints. Takes all the brush strokes or roller marks out of the finish, settles smooth like a plastic finish.
Nice High end look to it. Excellent Products, you may want to think about it!
I am a huge fan of clean and scuff for the cabinets...maybe even wipe down with wax and grease remover. I think PPG is MFG I think. It is a automotive Final Prep to remove oils from your hands in the final prep.
Maybe, just a Good old Wipe down with a 5 Gal bucket of Dawn Soapy water and scuff maybe is all you need?
Even if the first coat goes a little crazy, let it flash/dry a bit and roll a thick coat on top and is will probably straighten out and dry right.
I am Also a Huge Fan of Sherwin Williams "Duration" Product Line, Egg Shell Finish. Egg shell or the Satin Finish will give you that plastic tougher look and feel to it.
I would not get a "Flat Finish" as it will be to chalky and not a tough paint that will want to absorb splatters of RVn.
SW Duration= 1 coat Coverage beautiful Quality paint.
Make sure you hit the upcoming yearly Nov-DEC time frame -40% sale will be coming up.
Best Paint on the Market. I painted my San Antonio House Interior before I sold it. Everybody Loved it. Silverplate and Tin Lizzy.
Also use their Colorfast App. Take a pic of your wall and apply their color to it. Cool feature. Also the app pairs up the 'Matching" accent colors, or you could always buy the 7 buck quarts to actually apply to you r test area.
I would also go light so you don't make the walls close in on the RV by going Dark. Dark and Small spaces are not good.
Silverplate is a little cold looking but I loved how it made my house look, SP along with The darker Tin Lizzy on Accent doing the cabinet doors with TL.
SW has some Beautiful Shades of Gray and all colors. I Would DEFINITELY go a interior "Satin" Duration Line on those walls.
A gallon would do every wall in the RV twice over easy with plenty left over for continual touch ups.
Just My $0.02.
JD