Breastfeeding of an unknown number and the breastfeeding that establishes prohibition

Question:
My brother and I married two sisters. I was blessed with a daughter, and my brother was blessed with a son. However, my daughter was breastfed by her maternal grandmother, and the number of breastfeedings is not known. Is it permissible for her to marry her cousin, who is also her maternal uncle’s son?

Answer:
If a child is breastfed by his maternal grandmother, he becomes a maternal uncle to the children of his maternal aunts. If he is breastfed by his paternal grandmother, he becomes a paternal uncle to the children of his paternal aunts. Therefore, marriage is not permissible. However, if the breastfeeding is not precisely documented and the number of breastfeedings is unknown, prohibition is not established. The breastfeeding must be precisely documented as five times, or more than five breastfeedings, or more. This is the breastfeeding that establishes prohibition. If the number of breastfeedings is unknown, or if it is less than five breastfeedings, prohibition is not established.

Question:..

Answer: This falls under the category of "leave what causes doubt," but it does not become forbidden. It is merely a matter of doubtful matters, and leaving it is better.

Question: Do you distinguish between them?

Answer: If there is doubt, leaving it is better. If they are confused about the number of breastfeedings, leaving it is better. However, it is not forbidden unless it is precisely documented.