Why two lights set to 5600 K can render skin differently
Separate source temperature, camera white balance, tint and mixed illumination.
Source color and camera correction are different settings
A source temperature describes the light; camera white balance establishes how that light is interpreted as neutral. Under a warm source, a daylight white balance may leave a neutral object warm. Matching the correction brings it closer to neutral. The patch below illustrates direction, not a specific camera response.
A neutral-patch workbench
A gray reference replaces a face. The RGB patch is an approximate illustration of color-temperature mismatch.
Kelvin does not describe the whole spectrum
Two LEDs set to 5600 K can differ in spectral distribution and render skin or fabric differently. Green–magenta tint may remain after temperature adjustment. CRI, TLCI and SSI are different reference metrics; one number cannot guarantee every camera–subject combination. Test a neutral reference and the subject at the intended output.
Mixed light can color the two cheeks differently
A window on one side and a warm room lamp on the other create separate color regions that one global white balance cannot both neutralize. Choose a dominant source, then switch off, block or color-match the other. Warm background lamps may remain if their spill does not stain the skin.