I think logic answers this one nicely. but the effects of stacking may have a different result than people might expect..
Say the NPC does indeed have those two conditions in place... and by rolling twice (both conditions are VERY specific about this point) and considering the results the GM does meet those requirements. (considering the result is the second specific action required) What if there is no lessor value? Say the result of the dice were a pair of 16’s. Then, after considering once, the GM might have to make a 3rd roll?
Seems silly, but that would be the only conditional ‘stacking’ effect I can envision.