RV built with hole in the Floor (Thor/Four Winds/Mandalay)

I think the weird thing is there are 2 to 4 bolt holes around the larger hole. This make me think in a different model that panel is used differently and something bolted through it. I would just get a sheet of steel from somewhere maybe even Home Depot and bolt it over the hole. although that would leave bumps from the bolt heads. You could probably just duct tape the parch down as the carpet and padding will hold it down once installed.