I may not be much help, but I can offer my very recent experience.
A week ago Sat, my 2 mo old filly, No Disguise, split her upper eyelid open while I was body clipping her. My regular vet was out of town, so I called the equine clinic closest to me. The vet there came out and sewed up her eyelid. All looked good for a couple of days, then she managed to get her sutures out. I took her to the clinic last Tues to have the eyelid re-stitched. The surgeon there stitched her back up and sent her home. Inistructions were no banamine, no systemic antibiotics, leave her outside and just put antibiotic ointment in it a couple of times a day. By the next day, the eye was very infected looking and very swollen. I upped the antibiotic ointment to 4 X day, gave her some banamine and finally got the worst of the infection under control. But by Friday, I still didn't like the way the eye looked as it was still swollen and I thought the eye was looking cloudy.
I called my regular vet who was back in town, but his truck was in the shop and he couldn't come out. He thought it sounded like the eye needed to be seen again. I ended up taking the filly back up to the surgeon who did the last repair. His main concern was the eyelid and sutures. They were still intact, but he did stain her eye and said it had a small ulcer. But again, he wanted the filly to stay outside, antibiotic ointment every 2 hours. No indoors, no atropine, no banamine, no systemic antibiotics.
Saturday my regular vet was out, took one look at the eye and said "forget the eyelid, we need to treat the eye!". She had a rather large corneal ulcer, so she is confined to the stall by day, out at night. She is getting atropine, 3 kinds of antibiotics to the eye, systemic antibiotics, and banamine for pain and inflammation. The eye is looking much better now but she has the sutures out of the eyelid. My vet said not to worry about that because he could do cosmetic surgery on that later. The eye itself was his biggest concern.
So, I'm not sure what we will do with the eyelid at this point. It is not as separated as it was initially, but I'm not sure how much will heal and fill in on it's own. So that's my experience and I really don't know what to tell you other than my little filly has had a very painful time and still has an eyelid flap that may need treatment later.