Well if someone wasn’t following procedures then I suppose anything is possible. But the general premise of the article (that ‘fumes’ are making their way back into perfectly good buildings via the plumbing) is problematic.
They never once implied the fumes were entering via the plumbing.
In fact I will quote: "Emissions from a nearby CIPP job got indoors through cracks in the building’s foundation and irritated workers to the point that they evacuated"