I tested the soviet replacement soldier and indeed i just noticed that as you say he does not show through a PAA window despite using a PAC texture, while the the soviet officer replacement that use exactly the same texture shows perfectly in the window.
That's really strange, because i can't see what i have done differently for both soldiers.
When i built them, it was a same model with a naked head, i merged it with a helmet model (and every of its already prepared lods) that was already prepared (that was using the same texture as the base model) on one and saved it after making sure selections were correct.
Then i took the model with the naked head and merged it with the already prepared beret model (that was using the same texture as the base model), and saved it.
Then binarized the both of them.
So in this process i did absolutely no extra step for any of them, so there is no reason the faces would have all gone in bottom (and when i tried to "face on top" another model that was going to the same window bug, it did not solved it anyways) for one model and not for the other.
Why the building window PAA transparency works for one, and does not work for the other is beyond me.
In the side the BIS small fence that can be seen around one of the house does not appear either if you look at that building from the window.
So is it really a problem on the models(fences, soldiers, vehicles), or on the building and window one ?