So sorry to hear of your problems with Harlie.
We took on a Malamute Malaki a couple of years ago.
We had him for 6 months but eventually had to pass him back to the charity we got him from for exactly the same reasons,
fighting with the other 3, guarding and posessiveness.
He did some serious damage to Darwins leg, that was the last straw, and I think that's where Darwin gets his aggressiveness towards other dogs from now.
We had 2 1/2 years of non stop fighting between Echo and Darwin ( I even got bit trying to separate them) but we toughed that out,
but Malaki was just too big for the other guys to defend against
Sometimes it doesn't work out.
Big hugs for trying.
However she may say she's pedigree, but without papers to prove it. . . she's not.