Def not ply. It's printed banding that looks like ply. It is a very good look a like. I've tried to get a better picture for some reason can't get much better than that. I suspect it is a bit crumbly, the black bit behind the banding. My idea is, once bone dry, mix some wood glue and pine saw dust and push it in along the line, and if an warm to hot iron takes the curn in the banding out, seal the edges back together. I doubt it could look much worse. try it on a 10cm long section and if it works do the rest.