Is a person sinful for not going to Friday prayers in centers where he sees doctrinal deviation and partisan bigotry, fearing that the prayer will not be accepted or that he will fall into discord?

It is not permissible to abandon Friday and congregational prayers behind an innovator unless it is possible to pray behind someone who is in a better state. Otherwise, you are obliged to perform Friday and congregational prayers with them, unless their innovation is considered an act of disbelief (kufr). It is obligatory to ascertain their falling into innovation before issuing judgments.