@bbybackfat usually the confrontation is very crude. with the recipient of that horrible enlightenment (people in Robia's circumstance,) lose all their brain cells and rush to confront the person. this has substance BECAUSE our protagonist was tested and outwitted, not only that Robia is someone that we have always been suss of, not a main love interest. his deduction has been omitted and was mentioned at the most essential time, when he has undeniable proof that she is not who she seems to be, that she is more ignorant and unaware of her circumstances that the previous princess. the fact that Robia has been emotionally abused, doesn't change his intelligence quotient.
the reader is also played by the fact that the contents of his "test" sounds believable.
the original princess played a lot, poor Robia, his character essentially resolves around NTR.