Even if 82% upgrade passing rate is considered high or low by industry standard, I stand by my comment:
If EK operates with 1 Capt and 2 FOs on a lot of routes and burries the resting skipper in a remote coffin with guaranteed "no show" in case of a major problem, then the crew and passengers should only accept close to 99% passing rate at the upgrade. Else EK itself admits to a high probability that two pilots sit up front for a long time over remote locations with inadequate skills. No more and no less.
If such a high number of upgrade applicants display a lack of fundamental knowledge, then the recruitement AND training departement have failed. You need to recruit adequate applicants with sufficient basic knowledge and skills. Then you need to continue to train them as to have them "skipper-ready" when they take the left seat as relief pilots. The numbers seem to show that this is not the case. As simple as that.
Just what can we do to improve the situation?