Will Allah forgive a man who has a child out of wedlock, given his desire to conceal his situation, his dutifulness towards his parents who are unaware of the matter, and his fear for the non-Muslim mother of the child who might be harmed if he leaves her?

It is not permissible to continue a forbidden relationship with a non-mahram (definition) woman. One must hasten to repent with its conditions. The child born out of wedlock is not attributed to the fornicator according to the majority of jurists. Therefore, you have no relation to this child, neither in this world nor in the Hereafter. "Say, 'O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah. Indeed, Allah forgives all sins. Indeed, it is He who is the Forgiving, the Merciful.'" [Az-Zumar: 53].