Silicone is nasty--epoxy good idea.

Really like your idea about reversing the bolts--trick would be to line up the bolts perfectly with the pre-drilled holes---feasible since the one piece grudge on can serve as a template!

Will require me to retrieve the wood but bet I can do that with a long coat hanger or a dowel with a screw taped on.

Super answer---will let you know how it turns out!