Hi Carolina Mtn Gardener,
I'm not finding much info on insect pests and sedum.* You obviously have the larval stage of some pest.* I do find reference to black vine weevils, but the feeding habits of the larvae are to feed on the roots.* The adults do notch the edges of the leaves of plants, often making them look scalloped.* Do you see anything like that?
Here's a root weevil grub on a sedum.
Here's the damage.
I would definitely cut off the stems of any infected plants and destroy them.
When weeding, the best way to make sure you are removing a weed and not a valuable plant is to pull on it. If it comes out of the ground easily, it is a valuable plant.