Is it permissible for a young woman to marry her paternal cousin, knowing that her mother breastfed her paternal cousin's siblings but did not breastfeed him, and his mother breastfed the young woman's siblings but did not breastfeed her?

If your male cousin did not suckle from your mother, and you did not suckle from his mother, and there is no other reason for mahramiyyah between you, then there is no objection to your marriage, and you are not siblings through suckling. His siblings who suckled from your mother are your siblings, and likewise, your siblings who suckled from his mother are his siblings, provided that the suckling occurred within the first two years of life and consisted of five separate sucklings.