From your referenced picture, as I understand it, its also refered to as ... Blood knot
YouTube - UK saddlery, has a tutorial - entitled dog leash, and another called laced reigns as I recall. using this braid.
Hope this might help in your search ?
No I don't have an answer for you, As I struggle to find the same solution for my newly aquired shop bldg.
I'll be anxious to look over your sholder for an adiquate answer, Thanx for asking this question !