Looking at your pictures, I'd say not to worry. It's probably the adipose fat being concentrated by the compression of the belt.
I had a hole pop open about a week post op at the bottom of my surgical scar. For about a week, it leaked and got bigger. I consulted my surgeon, and he advised me how to close it.
From Amazon, I bought Vashe wound wash, Silver alginate, and Hypafix dressing retension tape. Every night I poured the Vashe into the hole in my stomach. Let it sit for a minute. Then used a paper towel to blot up the excess Vashe. Silver Alginate is like a felt material. I cut a piece that would fit into the hole. So, I carefully stuffed the alginate into the hole, then put a piece of gauze over the hole. Used Hypafix to cover it all. And every day, the hole got a little smaller. After 2 weeks, hole was closed. About 2 months later, skin filled in the area where the hole was.
When I travel outside of the US: I take my own syringes, Hypafix tape, Vashe, bandaid's, Silver Alginate, asprin, gauze, and plenty of Ostomy supplies.