“I began shooting eighteen years ago, using all four of the fingers of the right hand to draw the string, holding the arrow between the forefinger and thumb.” Will Thompson
I don't do well with confusion.
In all things there is an evolution. Will and Maurice began shooting the Sioux lock [note the above quote by Will], the same method Compton taught Young, Pope and others. It's a low anchor; just look at Young in some of his photos drawn.
When the hermit Thomas took them in tow and taught the boys the English method, they most likely changed to the split-finger. This draw is easier to move up the face than the Sioux lock. It is also easy to shoot low with this release.
Maurice notes in several places that in "point blank" or short range, he moves his hand up "near the ear," even on targets. At further distances he moved the anchor down low, taking advantage of "point of aim" at distance. Both were adept at changing their anchors based on circumstance.
I have a copy of a sketch Maurice did showing an archer drawing and pointing at an elevated target out of sight. Based upon the dress and all, the archer is likely afield. The drawing hand is low, under the chin. If it not for copyright issues I'd post it here, but I don't have permission from the family to do so.
Now, holding a high anchor or draw takes more effort and strength than a low, under the chin. As both became older, they anchored low because of strength issues; Will due to the fact he accidentally shot himself in the elbow in British Columbia which cause him a great loss of strength in his bow arm.
So, to do the best I can about the confusion, there is no "one" right answer nor any "wrong" answer.