Excellent point on the couplings. I’m not an engineer so I don’t know what materials they may have used for the gaskets, but is it possible one that passed QC had an unknown defect, or that exposure to solar radiation is causing it so slowly break down? Not to be The Harbinger of Doom here, I’m just spitballing - I’m sure this has all been vetted or is being looked at - but if they found deterioration in multiple couplers from a common cause......
well all gaskets that have rubber in em outgas over time
sunlight can help this accelerate
add in extreme temperatures and conditions
and that some have been up there quite awhile
thing is different countries made different modules
so you get the variations in vendors and suppliers and materials