This is the method provided by the exiobase consortium to us, but I agree, this looks strange. We'll check.
Edit: indeed, there were many elementary flows from non-combustion, which in the method excel were provided as such (like: "CO2, non combustion") while in the database, these flows are provdided as "from sector xyz" (like: "CO2, non-combusion, from cement manufacturing"), and because of that, these flows were then not automatically recognised.
We released today a new version (exiobase 3.4 version 2) where this should be fixed.
Best wishes,
Andreas