Hi Susan,
I’m sorry to hear this happened to you. How frustrating!
At this point, you need to go into it with the idea that something is likely to be ruined – your table or casting or both.
Try adding boiling water or a heat gun to the base of your casting where it meets the table. The idea is to soften it up to allow you to use something like a screwdriver or paint scraper to get underneath the resin and lift it up. It may take five to ten minutes of ‘heat’ exposure to get it soft enough to lift up.
Good luck!