SR71:
The charts go through various stages of "checking" before final submission and maybe that plate got missed?
This problem obviously lies with the source. Having said that, Jeppesen used to be better at challenging such discrepencies than they are today. I need supervision, too, I reversed the IAPs in my previous post.
In terms of the physics, isn't the main reason for using a backcourse procedure for the MA here, because, tracking with accuracy is most critical early on in the MA procedure where you are close to the ground and when using a beam radiating from the location of the I-PKN, you gain that accuracy where you need it?
That sums it up. Nothing else would provide the navigation accuracy required to miss some really high terrain during, and just after, that missed approach turn. It is not nearly as critical for the departure procedures.