Let me know how it works on them if you can remember. BTW, I just looked it up online to be sure and NAA (1-naphthaleneacetic acid) and IBA (indole-3-butyric acid) are the two common auxins you find in rooting hormones/accelerators. Might find them both listed on the active ingredients list on the bottle. I have no idea which might be better or worse for this application. But if they aren't growing it's probably worth the try.
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Actually, this is kind of funny but I just grabbed an old bottle of Miracle Gro Fast Root Rooting Hormone from my closet to check out of curiosity and it lists IBA as the active ingredient. So shouldn't have any trouble finding that.