The reason I feel the subject sheath is one perhaps cut out by HKL and finished by Johnson is the stone flap.
The Heiser BB flaps were more blunt on the tip.
The Heiser/HKL BB flap blunted
The Johnson BB flap more pointed
Not much has been made over the flap shape over the years, but as each maker had dies to cut out the sheath pattern, they also had the die for the stone pouch. With very few exceptions of perhaps being worn, I can tell by the shape of the flap tip whether it's Heiser/HKL or Johnson Brown Button.
The brown button sheaths from Heiser thru HKL exhibit that blunted tip on the flap. Though the tooling appears to be pointed, the leather edge is blunted. See example below.
This is an HKL BB flap front and back
Here is a Johnson Baby dot front and back
Here is the HKL and Johnson together
Following is the front of the Johnson BB pictured above, with the Johnson Baby dot, virtually identical.
Here is a picture of the subject flap in the center, with an HKL flap to the left, and a Johnson flap to the right. Which one does the center more resemble, HKL or Johnson?
Again the subject sheath has attributes of both HKL and Johnson, thus perhaps
1) started by HKL and finished by Johnson
2) HKL sent dies to Randall, Johnson used them and duplicated the sheath including West stamp, then within weeks or months retooled and changed dies while still doing BB sheaths, and changed stamp orientation to East.
If Johnson made the subject sheath, he used HKL dies, and it was an early Johnson, because he had new dies made and changed stamp orientation while still doing the BB sheaths.
Again just an opinion, fun to speculate on these old ones.