Delete the file "ex_prop_ex_office_text" in

mods\update\x64\dlcpacks\mpexecutive\dlc.rpf\x64\levels\gta5\props\int_mp_h_accessories_ex.rpf\

*Remember to backup your files* 

Next download Addonprops and place the prop in the props.rpf.

Then add the prop using props editor and add the prop, set the LOD to 500, and for textures select embedded.

(I had to do it this way because whenever I tried replacing the prop it would not show in Rockstar editor.)