Is a person who, for the purpose of obtaining a job under specific historical circumstances, attributed himself in official documents to another tribe—not out of disinterest in his original tribe—considered cursed if he is unable to correct his lineage later, or is his action forgiven?

The prohibition against an individual claiming a lineage other than their original one has been established, and Paradise has been forbidden for whoever claims descent from other than their father while knowing it. This indicates the disbelief of one who disavows their father and claims descent from other than their father, and whoever claims kinship with a people among whom they have no lineage, let them take their seat in the Fire. Allah has threatened with a curse whoever claims descent from other than their father or takes as patrons other than their true patrons out of disdain for them. It is not permissible to change the tribe's name except in cases of extreme necessity. If someone has done so or found it in their ancestors' documents, they must correct the error whenever possible.