Forgiveness of sins against G-d depend on being forgiven for sins against man?

 It is clear from Yoma (85b), Rambam and Shulchan Aruch O. 606 that Yom Kippur alone atones for sins against G-d. There is a view that Yom Kippor will not atone for sins against G-d  when the sins against man have not been resolved. Does anyone know of the source of this view which seems to contradict clear halacha?

Yoma (85b)With regard to one who says: I will sin and Yom Kippur will atone for my sins, Yom Kippur does not atone for his sins. Furthermore, for transgressions between a person and God, Yom Kippur atones; however, for transgressions between a person and another, Yom Kippur does not atone until he appeases the other person. Similarly, Rabbi Elazar ben Azarya taught that point from the verse: “From all your sins you shall be cleansed before the Lord” (Leviticus 16:30). For transgressions between a person and God, Yom Kippur atones; however, for transgressions between a person and another, Yom Kippur does not atone until he appeases the other person. 

Rambam Tshuva (2:9)   Neither repentance nor the Day of Atonement atone for any save for sins committed between man and God, for instance, one who ate forbidden food, or had forbidden coition and the like; but sins between man and man, for instance, one injures his neighbor, or curses his neighbor or plunders him, or offends him in like matters, is ever not absolved unless he makes restitution of what he owes and begs the forgiveness of his neighbor. And, although he make restitution of the monetory debt, he is obliged to pacify him and to beg his forgiveness. Even he offended not his neighbor in aught save in words, he is obliged to appease him and implore him till he be forgiven by him..