You should back up and learn to lead the difference between a foxtrot type reverse heel turn, and an open reverse turn (ie, not a heel turn). As in you should be able to get your partner to do one or the other without telling her which, as a result of differences in the movement of your body. That will give you the prerequisite skills to actually lead a telemark.
Then you should probably do some slip pivots (leader backwards).
Finally, you might be in the position to look at doing a leader-forwards reverse pivot without confusing it with a telemark. You might try doing it in tango first.
In practice, a lot of reverse pivots are going to be a conclusion to something else rather than a beginning of their own, and as such they'll coast with the momentum of the precede. They'll often also involve a degree of lowering from the ending of the previous figure (example slip pivot, quick open reverse and pivot, double reverse overspin, tumble turn, tipple turn, etc...). Outside of tango, one of these revere pivot endings to the previous is also going to be one of your more obvious ways to set up a couple more reverse pivots in the new measure - you'll just keep going with pivots. If instead you wanted to switch to a telemark, you'd have to catch the pivot type spin and instead drive into a heel turn.
