Yes, others (including myself, many years ago) have used a camera, but I do not recommend it for reasons given below. To be clear, any print-based linearization method, not just the QTR methods, face the same choices as to how to measure prints.
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First of all, you didn't say if you have a scanner. Even an inexpensive scanner will give you better results than a camera. Do you have a scanner?
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A scanner guarantees virtually uniform illumination. A camera + lights, unless you go to extreme lengths, does not. You say "This could be used to compensate for exposure and lighting." You can't compensate for uneven illumination. If you insist on a camera, I suggest getting one of the folding photo "cubes" used by people who photograph small items to sell on eBay. Get one with lights built in. I have one that I use for photographing finished prints (I don't have a scanner), so I can tell you that they're clumsy and take up space. A cube with all the bells and whistles will end up costing about the same as an inexpensive scanner.
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If you are exposing your prints in an lightbox that also does not provide uniform illumination, then using a camera to measure your prints, unless you take serious precautions, simply compounds the problem. The symptom will be iterations that do not converge quickly to linearity. The problem will be even worse if you are making digital negatives for a high-contrast process.?
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John Isner