Remember, though, that the weather was cold, there was snow on the ground and roadside meaning footing was less than ideal, and she wasn't wearing winter wear. That greatly decreases the amount of ground she is likely to have covered, I think. I did a quick check, and if she did indeed head north, and she stayed on S Rockerville Rd (rather than go off the road onto a little road or into the woods or hills), it is still over a mile from the compound to the nearest house. By then she would have been getting desperate to get warm.
I hope the Home and all homes along S Rockerville check all their buildings and out-buildings (like sheds) again, very thoroughly, in case she crawled into a corner somewhere.
As for nobody seeing her, I don't think there is much traffic on that road. And until she gets to that first house, and for most of the road after that even, there is nothing. Nobody would be around.
Sigh. Five days in that weather is ... unthinkable.