Yuck, but diff oil colour aside, was there any crud (bits of clutch pack material and metal) in the bottom of your oil drain pan after the process?
I'd think some oil would be stuck to diff walls, clutch packs and gears so not all comes out but how much is left in i have no idea
(Some also pump a little clean oil into diff and let it drain out to flush any remaining crud, though probably not needed other than it sooths OCD
)
Since you had just the rear lifted, and maybe a little bit of oil still within the diff, i'd probably would have considered only putting in what I took out. Than i'd check oil level when the car is on the level as i have no idea if overfilled is worse than underfilled for a diff.
Also, does extra diff additive need to be added (as warrick asked)? I always though LSD oil had the additives an LSD needed