i somewhat agree, and my speculation follows:
i believe that virgil has somehow possessed nero's arm, which would explain why the only thing it was really used to hold was yamato, virgil's prized sword
also, it is supported by nero saying that he heard his arm say "...power......i need more power.." or something which are also virgil's words that i think he said in the 3rd game
but anyways i donno, i also find it weird to see angelo in front of the names of some of the people in the order (nelo angelo)
i really don't know, some of the biggest plot holes i've ever seen i thought they would at least say something about dante's relationship to nero
let your anger be as a monkey hiding in a pinata, hoping the kids don't break through with the stick