I am FAR from melon expert - still trying to GROW them, really. But according to my experience with undersized ones, they do sometimes crack from drought-flood conditions when they are in fact not quite ripe.
I've had some success with those by wrapping with one or two layers of paper napkin or for larger fruits, cotton bandanna.
Typically, without wrapping, some stray fruitfly or ant or maybe even mold spores can get in the crack and they can spoil rapidly.
I didn't know you could ripen melons in the refrigerator, so I would wrap them and put them in a basket on the counter.
Did you mention what variety these are? I'm enjoying your enjoyment of them.
I believe only cantaloupe variety I'm growing this year is Honey Rock Melon? I also have Snow Leopard which I think is a kind of honeydew and Korean Melon which is supposed to be a prolific bright yellow oval-shaped smaller melons with light color along the grooves of the lobes.