Which is the real Achillea holosericea?

I grew seeds of Achillea holosericea this year, and ended up with two different plants. Most of the seedlings look like the plant on the left, which I suspect is not Achillea holosericea, judging from the few photos I can find, including the one in the article by Grahame Ware in the spring 2012 Rock Garden Quarterly. (It does look very interesting though!) Can anyone please comment or suggest what the one on the left might be (if it not Achillea holosericea)? Thanks.