I don't think dilution is a good idea, but others may have some real experience with this.

You can store exposed film in a refrigerator for 2-3 months without any degradation whatever. Seal the film into a freezer container or ziploc with a bag of desicant list silica gel. If necessary, dry out the silica gel in an oven and let it cool before placing it and the film in the sealed container. Most camera stores sell packets of silica gel that have an indicator that turns different colors to show when the packet needs drying out.

Most important, when removing the film from the refrigerator, let it warm back up to room temperature before opening the sealed container. I allow several hours, just to make sure. This will prevent moisture from condensing on the cold film surface.