Is it permissible for an Imam who suffers from severe nasal allergies, which worsen at the time of Fajr, to pray Fajr at home?

Attending congregational prayers in the mosque is obligatory for men, and whoever abandons it commits a sin, especially if he is an Imam who receives a salary for his Imamate, unless there is a legitimate excuse such as fear or illness. If the Imam's going out at the time of Fajr prayer causes him an allergy, and there is no way to avoid it except by not going out, then he is considered legally excused for not attending the prayer.