I've seen them split from a rubber band only. Use Joy's method. Run a toothpick 1/8" or so thru the bottom of the stalk, then have the rubberband on each end of the toothpick and under the rock. In maybe two days, it'll attach just fine. I've done it a hundred times.
Don't worry about the glue. After 5 seconds, I'm betting there was no trace of glue on that wet, slippery fellow anyway.