ok, good description… Im starting to wonder if what you are seeing might be the Tint of the XP-L Hi 3A, rather than tint shift.
maybe it is normal that the tint is most noticeable in the spill, while a hotspot looks white because it is intense
Here is the Tint of an XP-L Hi 3A that maukka tested.
Notice the X marks in the yellowish tint area on this chart:
