Ah, but these are 6011, not 6010 - not familiar with these (they just brought me a box) Same scenario? AWS D9.1 section 1.4.4.2 says dried for 2 hours between 500 and 800 degrees F for A5.1 rods (which these are).
And you are (probably) the first to have ever checked them on this this ... 8<)
What diameter rod are they trying to foist off? If they are attempting to weld HVAC-thick sheet metal with SMAW, it will have to be very, very small or they will burn through. Also: Stick welding is notoriously dirty and leaves a lot of grit, debris, and residue. Have they (the welders) committed to cleaning up and wire-brushing the interior AND exterior of the sheet metal before air flows through?
Have you inspected at the end of each shift the interior and exterior (before insulation goes on!) to make sure it really is welded up properly and cleaned?