Ilya Treyger, in the past the active participant of Smolin seminar on cryptozoology in Moscow, nowadays he lives in Denver, Colorado, USA:
Michael, congratulations! You have worked, as professional expert in photo. I could not carp to any position in your report. Except for, perhaps, this - I would not do the statement, that feet are four-fingered. You, probably, noticed, that people have knitted fingers not too seldom. Usually the second and third fingers on legs have such form. It is due to genetic peculiarities of human. This is a rudimentary phenomenon. Most likely, it is knitted two fingers, instead of one...
But, this is my personal opinion. As fact, you could not tell for sure, all depends on a track.
I see only four separate fingers for both copies in the print, therefore I named feet as four-fingered. In our collections there are casts and prints with precise four fingers, and all of them are left by giants. But there is no one among them with such characteristic of fingers - two large and two small weak on the same foot, that received on the territory of the CIS.
In my opinion, your assumption, that the second fingers of the feet represent actually knitted second and third fingers of a five-fingered feet, is quite realistic. But there are also other possible ways to come to such form in development of obvious narrow specialization - fingers of the animal, climbing in rocks. It is easier to use the pair of strong fingers to cling to small ledges and cracks in rocks, than foot of the human form (think about mountain goats).
These additional ways are:
The first is loss of the big finger if the initial form for specialization was an apelike foot with a big finger removed aside.
The second is loss of a little finger during a continuous reduction of the third, fourth and fifth fingers from the form with already joined tomb.
What of these three possible ways really occurred, whether it became the specific feature of the species, it will be possible to solve only after studying a foot skeleton of these hominoids.
But we must not act as anthropologist Vladimir Chernetsky. He had added to the foot the fifth small finger contrary to what was seen on the image and had tried to reconstruct foot and general view of the animal on the deformed basis. (see. R.Izzard. On traces of the yeti, 1959. In Russian, The appendix.)
Yes, Michael. Everything you speak about is quite reasonable and corresponds to biological principles of body transformations. All this could be accepted, if the question does not concern fingers particularly. The matter is, as far as I know, that in the nature no any four-fingered animal is found till now (I mean really four-fingered). Even in such cases of a reduction of fingers as horse hoofs and the bird's wings, all five fingers nevertheless are present in skeleton. Fingers have absolutely unique position in biology.
I am not so strong in this theory. But I very much cautious to speak about four- fingered leg.