Is it permissible for a mother to go for 'Umrah with her paternal cousin and his wife if her husband and brothers are unable to go with her?

Among the ways Islam protects women is the obligation for them to travel with a mahram to safeguard them and protect them from base intentions, and to assist them during travel. It is not permissible for a woman to travel without a mahram, due to the Prophet's (peace be upon him) saying: "No woman shall travel except with a mahram." Scholars have stipulated five conditions for the mahram: that he be male, Muslim, an adult, sane, and a permanent mahram (one with whom marriage is eternally forbidden), such as a father, brother, paternal uncle, or maternal uncle, and not like a sister's husband or paternal aunt's husband. Based on this, her husband's brother, her paternal cousin, or her maternal cousin are not mahrams, so it is not permissible for her to travel with them.