First, thanks for providing enough information so the question can be answered. As dumb as that sounds, it does seem to be a problem some times. I can't speak for any engine MOD since I don't use any, but I'll give you my take on the question, and it's only my take.
The variables you seek are not available to the player. They are hard coded into the engine and we can't see where the player is or where he is looking. Actually, I don't think where he is looking is even tracked at all.
In order for an entity to move the way you want, it will have to be made into a character. It's nearly if not impossible to move entities on the fly. Characters however, can be moved by the commands you referenced above. Turning an entity into a character can be as easy as adding
IsCharacter = 1 into the entities FPE file. Using the condition
plrdistwithin in conjunction with the movement commands for entities should allow for at least some of what you seek.
Best.