i see. the profile is not irrelevant imo.There’s a damaged part - an OE DIN bubble flare, and an OE line nut. The line nut has squared shoulders of the inner diameter where the flat bottom of the DIN Bubble would sit.
Every single part from manufacturers has that taper in the inner diameter. They all claim to fit my vehicle, all claim to be for European vehicles, etc.
Either the significantly reduced contact area on the flat backside of the bubble flare is irrelevant, or every single part sold anywhere that I’ve looked is wrong.
Well they verified that the bubble flare nuts have the squared inner diameter shoulder. So I fuel I’ll get the right thing…
would it leak, probably not, is it correct, no.
good luck. it would seem you are going to have to compromise on something......