Is the young man who had a relationship with a girl that resulted in pregnancy, and provided her with an injection to abort it, then she informed him that she had aborted it dead, considered to have committed the sin of killing a soul, knowing that she is contracted to him but he has not consummated the marriage, and is he obligated to pay a "ghurrah"?

This young man must sincerely repent from fornication, especially since it was with a married woman, and repent from assisting the woman with the abortion, because merely assenting to a sin makes its perpetrator sinful. As for the responsibility of guaranteeing the fetus, it falls on the one who directly carried out the abortion, not on the one who suggested it or assisted in it.