That almost looks like a double hose clamped. Not right if it is.
To possibly save some time, why couldn't you take the corrugated flex off, make a step UP aluminum tube piece and connect it, keeping the radiator and tube diameter the same and the water pump inlet the same as well.The original setup that factory five provide worked for quite some time. It was made up of two hoses at the radiator outlet. An inner rubber hose that brought the diameter (kinda like a sleeve) up so it would match the Steel Hose and the larger rubber hose that would slide over both the corrugated steel hose and the hose over the outlet. I did notice that the outlet on the radiator has a slight "dent" inward, but it's before the "bead"( between the bead and the end of the outlet) so I wouldn't think it would have an effect. I have removed ( it was just ugly anyway ) what was in the picture and going back something close to the original setup. If it still leaks, I'll take the radiator out and take it to a shop to see if there is a defect or crack that I cannot see. I'll let you all know how it turns out.