I’m not a lab technician, but typically a qualitative test is only done when a test is positive or abnormal. For example, in pregnancy testing, HCG levels wouldn’t be tested if the pregnancy test was negative. In fact, it wouldn’t be practical, since the hormone level would be zero or close to that. I don’t know if the same thing applies to G6PD.
It sounds like you need two tests, one for positive/negative, one for units of measure (the level) of what you are testing. I would call the lab from another hospital that is similar to yours (or uses your LIS), and ask for their advice. You also want to ask your own lab manager if both tests (qn and ql) are tested from serum or whole blood. They may be different.