It all depends on the elder body. There is nothing in the publications directly saying that taking yoga would result in DFing. I wonder if the secret elder's book has anything?
On a related topic--Tai Chi--how many know that it is the first level in Karate?
Several older sisters had signed up for it when I was still a good Dub and I mentioned that to one of their husbands. He said I was wrong...so I looked it up on the Internet and showed him where it was...of course, they didn't quit their classes saying that they weren't practicing false religion.
So it depends on the opinion of the elder body.
Blondie