Do a little research in the Ski Tube tunnel, Research what Kumagai Gumi and John Holland did when the roof gave way 70% up toward Blue Cow Ask how the Japs used bails of hay to fill the void
The CONTRACTOR knows (or should do), in the case of a stoppage, and if they didn't know they should not have got Turnbulls "go ahead"
Instead of being a keyboard warrior, trying for peer points, make sure of your facts before the goose tag hits.