As a professional engineer, my advice is to stay on the landward side of the crack...
We could soil pin that rock back together. Where is your sense of professional adventure? We are going to need an anit-gravity platform to support the hydro rock drill. We could anchor the cracked strata with a tractor beam while we pin the masses together with unobtanium and epoxy.
Don't forget, we now live in Utopia. Anything is possible.
I need more information before I decide if your advice is valuable. Are you an ME, EE, ChemE, Petroleum Engineer? If you're not a CE, then I question your qualifications to render such advice.
5,000 gallons of Crazy Glue could do the trick. Don’t use Gorilla Glue though, it expands as it cures. Bad deal.
PS... don’t build near over hanging weathered limestone cliffs.