I don’t know how much the rod goes into ferrule, maybe you could trim the ferrule and rewrap. If it were me I’d remove the flex-coat and see how far the cracks go up the rod, the crack that you have posted looks as if it was not fitting well to begin with. I would remove the flex coat on the wraps with my Dremel tool just down to the thread which will make it easer to peel the rest off, after clean up I would coat the cracked area with a very very thin coat of epoxy and let it cure. Finnish the repair with a bottom wrap of size A thread and a top wrap of size D thread and coat the repair with a high build flex-coat, don’t loose you rods alignment dots. If you don’t have a Dremel around break out the hair dryer to warm up the flex-coat finish and use a utility knife to slice through it, take your time, and always wax your fittings before you put the rod together. I hope you can get some more life out of the rod.