Just another recent map showing half of the heavy gunners
https://pasteboard.co/GGSEQoA.jpg
I wish map makers would upload the complete textures when modding soldiers
Unfortunately, map makers can't upload the textures as they're intrinsic part of the mods they're using.
Perhaps having Predaaator's mod installed will fix the invisible soldiers: http://www.nexusmods.com/farcry4/mods/33/