Is it permissible for four people to establish Friday Prayer, with a congregation and a sermon, in a private place, if the only available mosque is far away and contains innovations and is unhealthy?

Jumu'ah prayer is obligatory upon the residents of a town if it is established therein, and it is not permissible to be absent from it except for an excuse, even if they do not hear the call to prayer or if their homes are far from the mosque. It is not permissible to establish a second Jumu'ah prayer in the town as long as the mosque accommodates the worshippers, because the multiplicity of Jumu'ah prayers without need is not permissible. Jumu'ah prayer is not waived due to the Imam's innovation (bid'ah) or wickedness (fisq); rather, it must be performed behind him. To solve the problem of innovations, those in charge of the mosque must be advised in the best manner. However, if the place is unhealthy and it is highly probable that worshippers will contract an illness, then this is a permissible excuse for not attending Jumu'ah. Jumu'ah prayer is not valid with four people according to the majority of scholars; the Shafi'i and Hanbali schools hold that it is valid with forty, and the Maliki school holds it is valid with twelve or more.