@Stan Galat I was wondering if a gear clamp, the good ones, with sometype of sealant could be done to completely encase the joint and seal it. Kind of like molding a rubber or sillicone encasement. Ear mold silicone the stuff is like unbelievable in keeping a shape.
The hose is the major hose coming from the engine and I am sure that I would have a lot of fun to change it. Just saying.
So-- short answer is, "do you have any confidence of these various repairs holding 250 psi in a vibrating and hot condition?" I don't.
As you know, the crimped connection is leaking. If you can fit a hydraulic hose crimp set-up in there, you might be able to re-crimp it. Alternately, you can cut it off at the end of the collar, and try to cut the ferrule off of the fitting, get another ferrule, push the (shortened) hose onto the fitting, and re-crimp the new ferrule.
... or just bite the bullet and get a new hose.
The question isn't "why is it leaking". The question I have is why some of them don't.