I think you are spot on. clamp the mold over the ropes and figure how to squeeze it in there.@dspacio Thanks for your insights and experiences
My idea for a glued splice is to use an adhesive that is much more flexible than an epoxy. More like what we know from silicone adhesives or sealers.
The 'how' of this in my vision is a two part mold that holds the rope in place. Then there are injectors that squirt the glue into the rope, surrounding all of the fibers. Vacuum and pressure injection seems to be the way to distribute the adhesive.
That's the first thing I thought of.