Get a knee high stocking (panty hose type), cut off the toe and cut a hole for the good wing, not too big, just enough to get the wing through and fit closely around where it joins the body.
Now, fold the angel wing in place so it looks normal and slip the hose over the body and put the good wing through the hole you made. Make sure the hose fits snugly around the body, but not so tight as to restrict breathing.
Check it every day to make sure it remains in place. After a week, take it off completely and leave it off an hour or so to see how it looks and to let the duck flap and exercise. THen put it back on for another week. Repeat for 3 to 4 weeks and hopefully it will fix itself.
At six weeks, you will probably only be able to correct it a bit, but it is certainly worth a try, you never know....it may correct! If it doesn't work, the duck will be fine and it will not affect him at all.
What are you feeding? It may be that the protein is too high. If you still have them on starter at 6 weeks, it is time to lower it to a 14 to 16% all purpose feed. Layer feed is too high in calcium and may compound the problem.
