What sort of floor material do you have in your brooder? If new chicks can't get good footing early on, spraddle leg can be hard to treat. We put cloth bath towels (hand towel size like you'd use at the sink) in our brooder to give chicks very good traction for building strong leg muscles.
In your photos, the band-aids look a bit too big to me as well. When we've done band-aids, we cut both ends off a stretch fabric band-aid, then lay one piece sticky side up on a hard surface like a counter and place one foot on that piece of band-aid with the leg pointing downward to one edge of the band-aid. In other words, we're making sure that there isn't a lot of extra material toward the back of the foot where it's not needed.
Once the foot is placed down, we start at one side gently adding the second piece and trying to get it down between the toes to hold them in place by sticking the band-aid top to the bottom piece. Work your way over to the other side of the foot.
Once you've got a bit of a mated seam all the way around the front and sides of the foot, trim that seem to leave enough band-aid stuck together around the outer edge to hold it in place, a little less than 1/8". The toes pointing in an outward direction along with the adhesive holding around the perimeter and between the toes will keep the pieces in place.
It's REALLY important that the chick has good footing in the brooder, especially with a band-aid on the bottoms of its feet. In fact, that's important for ALL chicks to build healthy leg muscles. For your spraddle leg, you can even use strips of the band-aids WITH the center pad to cut strips for binding the legs together to cure spraddle leg. Creativity in the method is unlimited.