but the fuselage issue being structural and pressurised menas that if it goes the whole lot goes in one go?
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And if it delaminates somewhere unpressurised does this mean that it could do the same somewhere pressurised?
I do not understand your osession with the pressurized part of the aircraft. Delamination is failure of the laminate perpendiular to the fiber layers. If loaded in tension, the effect is minimal as the fibres will keep straight and be able to carry a signifiicant part of their ultimate load. Only in compression the fibres will buckle and the strength of the part is significantly reduced, most probably below limit load capability.
As a pressurized fuselage creates tension in the skin, delamination in the pressurized area is not critical. You will probably first have a problem to maintain the fuselage pressurized due to the air leak before you reach any critical strength condition. I would be more worried about delaminations in the upper wing skin where it under extreme compression. And so did Boeing when they found issues there.