If you want to split them, try teasing them apart Very Gently. That will tell you if they are ready. If they come apart easily, maybe allow them to callous a day or two before replanting. Otherwise, if they resist separation then plant them back in together.
The stem roots will be removed with the stem stub later. No worries there. Don't strong arm the stems out until they are loose and ready to separate. This will be quite a while later. Keep an eye out for bulblets, though I don't see any offhand. Silk Road is pretty tough and as you can see, vigorous.
And as Lynda recommends, mark well the places you plant them and mulch.
