What is the ruling on someone who leaves their house while in a state of major ritual impurity (junub), and what is the means of convincing them to refrain from doing so, and how does their state of major ritual impurity affect those with them in the same place?

It is not forbidden for a person in a state of major ritual impurity (junub) to leave his home. Indeed, Abu Hurairah (may Allah be pleased with him) once went out while he was in a state of janabah and met the Prophet (peace be upon him). His state of janabah has no effect on those sitting with him. What has been reported regarding angels not entering a house that contains a junub person is not authentic.