Can you do a proper reverse grab to begin (flying body spiral)? Can you get into twisted ballerina (pretzel) statically?
This move, at least for me, requires quite a bit of shoulder flexibility in order to get your body in front of the pole to be able to wrap the leg. If you are not getting your body completely in front of the pole before you grab with your hand I would suggest working on that first.
You also need to have your body almost sideways across the pole. If you are still straight up and down you will not get this. Stop the following video at 17 seconds and look at her body positioning. You have to be THERE on your flying body spiral.
http://poledancedictionary.com/moves/321/stag/