Sorry if this has been explained before (i am new to this discussion after all) ..how was our Broyles able to stand over the dead body of alternate Broyles? ..well i might be mistaken,but i'm sure that happened.
The alternate universe Broyles sacrifices himself to give Olivia time to escape the parallel universe and return to ours.
His body is sent to our universe by the parallel universe, Walternate I believe, as a substitution of mass so that Fauxlivia can return to her universe.