It's hard to tell exactly what is going on from your images, but the one thing that is fairly clear is that you have had separation of the incision around the belly button. I agree that there does not appear to be infection, but it is hard to tell for sure if the belly button is totally necrotic (dead) or not. If I had to guess I would say it's not because I can see some pink tissue at what looks like the top edge of it. If this is the case, wet to dry dressings as your surgeon suggests would be appropriate until the deep parts of the wound heal closed. I would expect this to happen, but it may take a few weeks. Keep an eye on things with your surgeon, and if you see some dead tissue or debris in the wound, keeping that under control with regular debridement in the office will help it heal faster. Once things heal, you can step back and see how it looks, and if things aren't to your liking a revision could be considered at that time. The main priority at this stage though is to simply get the wound to heal, and that will take time, patience, and meticulous cleaning, debridement, and dressing changes until it does. Good luck.