I have spare LPG cylinders in my garage. One trailer complete with LPG cylinders spends every winter in my garage. I also have about 30 gallons of gasoline in my garage in drums and jugs. But then on the other hand I also have fuel tanks in both vehicles which are in, wait for it, my garage! Oh, I forgot, I also have acetylene tanks in my garage.
My garage is detached from the house, I would be less comfortable if the garage was attached but would still use it as a garage!
If you are uncomfortable putting them in the garage, maybe take them off of the tongue and put them inside the RV out of sight.