Looking for advice on creating a scabbed wound.

It's done all the time with African animals. I can't see what you're dealing with so I can only explain the way I do it. It's better to go with it and make a convincing looking scab and scar than to try to make a repair that you can't hide perfectly. I use epoxy sculpt and add some color to fit what you need to do.Then sculpt it and build it up the way you want it to look.Texture it to what you want. Then slowly blend the colors. I hand paint it with oils beause you get a nicer blend and get little details in it. You've see scabs before. Try to duplicate one. Did you take a picture of the wound for reference so you can duplicate what you have? It can be done to look like it's from a fresh crusty cut with a little blood showing in the center of the cut to a healed up hard crusty brown scab. That leaves you with a broad selection of possibilities.