how many mods do you have enabled. If you go above 35, models start disappearing

You likely have more than 35 mods. To be safe, have a maximum of 33 mods. This includes any effect or movie files you download e.g. blood mods. These files do not appear in the mod loader. You could try using a third party mod manager such as this one to help you find out the issue or mod load order. https://github.com/Shazbot/WH3-Mod-Manager/releases

If you want a full hassle free DEI campaign you could try out my collection here. https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=3582860864

Hope this helps!