I would say the safest way would be to use a small piece of Bridal Veil material or netting and cover the polyp with it. Then with an elastic band secure the netting to the rock. After a few days remove the netting and it sould be attached.
I would not use any "Crazy Glue" but most gel super glues work well.
www.garf.org says that "Crazy Glue" is the only glue they avoid.
J