It's purposefully ambiguous.
so I think it will be explained on the following chapter. Spoiler: if I remember correctly duke ergi suggests/leads on that he might have messed with the test. & I think it was just left at that, then Emperor Soviesh is tormented by not knowing if she was or not his daughter. this was 2-3 years ago when I was reading a horrible translation of the novel. not sure how it end, but the way the story was leading I don't think he ever found out. which led to more of his downward spiral
If you need the ch it’s 181 were you find out who is the real father
I heard the emperor is NOT the father...then someone also said that he isa the REAL one. Can someone clear my mind? （/TДT)/