...in the wing. If it is not critical why is there enough load on it to crack it?
“Critical” has a different meaning in engineering terms. Engineers design redundancies in structures for this exact reason. There’s a whole list of parts on an airplane that the FAA will let you take off without, or at least without them being functional. Airliners are massively over-engineered. Twin jets have to be able to take off, land, and if they’re ETOPS fly for a hell of a long time on one engine. So arguably the second engine isn't even “critical”… although I’m not seriously suggesting that.
The Aviation Week article says: “Each wing has around 2,000 L-shaped brackets (30-40 per rib, with 60 ribs per wing), so the failure of one bracket is not seen as a safety issue.” These are the parts that distribute the aerodynamic loads from the wing skin to the rib/spar assembly. Essentially they’re secondary load bearing structure. If you have enough of them fail, you could potentially lose a wing skin section but the probability of that is exceedingly low owing to the shear number of brackets. I wouldn't start worrying till you hear stories of cracked wing spars or other primary structure.