Make sure you raise all the ground, it looks like from the previous picture you only raised the center. Ground that’s at a height the camera can show the top of will be visible (aka normal height ground that wasn’t raised)
In my last picture everything is raised, but I didn’t bake it. When I baked it again, it kind of seemed to work, and it looked fine, but when moving the character I’m not sure he’s moving, but maybe. He’s holding out his arms, so it looks like that old bug with not walking properly again.
EDIT: Despite all, I think I’ll continue on with my own solution to all this. Even though it’s easier to find the walkmesh helper ground in kamal’s solution, to add waypoints one still needs to lower the ground and rebake and all that hassle, so the way I see it, it’s just two solutions to the problem that both have their advantages. Since I’ve already placed my waypoints in my own area/solution, I don’t think I need to do anything more actually(we’ll see how it goes when I’m about to try out the actual fight, if that changes anything). Thanks for everyone who tried to help out. I consider this case closed…at least for the moment.