I added an inspection window I saw on another builders project.
I recommend you remove it and reinstall the solid inspection plate.
The RV-7 already has an problem with flutter of the vertical stabilizer and rudder if VNE is accidentally exceeded. Reducing torsional stiffness in the bay just forward of the vertical stabilizer spar just makes it worse.
Risk aside, the mod is pointless. I'm not aware of anyone reporting loss of a nut on the elevator tie bolt, ever.