Do you have a service manual?
Did you follow the service manuals instructions?
This video missed ALOT of important steps.
Just a few questions:
Did you clean off the splines and replace the Moly 60 paste on both pieces?
Did you replace the large O-ring on the splines?
Did you replace the small O-ring that is hidden underneath the spline plate?
Did you check the driven/flange bearings?
Did you lift the plate and check the conditions of the rubber dampers?
Did you use antiseize on the axle, or a least a good quality water proof grease?
Did you make sure the axle collar was seated correctly inside the pumpkin?
Did you TORQUE the 14mm head stopper bolt BEFORE tightening down the axle nut? (VERY IMPORTANT)
Did you check/clean/lubricate your rear caliper guide pins and inspect your rear caliper completely?
Did you remember to tighten the lower muffler bolts once you were finished (often missed)
Did you inspect/replace the rubber muffler hanger grommets (normally damaged from dealerships service)
Did you test the secondary master cylinder for correct function after removing/replacing the rear wheel?
I could go on, but I think you get the idea