Well people clone like that all the time, so you should be ok. You might want to check up on some cloning techniques to be sure to keep that stem alive.
PS. It looks like you have a bad deficiency in your plants, probably Magnesium it looks like. In Magnesium def. the veins of the plant remain green while the rest of the leaf begins chlorosis, leaving the leafs looking exactly like yours. This starts in the lower leaves and travels upward. This wouldn't be so bad except for the fact that a lack of Magnesium can hinder the uptake of Potassium, something you don't want during flowing.
You can fix this with a tablespoon of epsom salts per gallon the next time you water, and a teaspoon a gallon at subsequent feeding.
I wouldn't start flowering those girls untilll you take care of your def., you buds won't be near what they could be if you dont.