Need help identifying UE4 Space hulk texture maps. (_RGBa)

Kuroyasviel

Sorry if this is in the wrong section, new here.(If its the wrong section can a mod please move it to where it fits?)
 but I've been trying to figure out what these maps are from Space Hulk: Death Wing, a game running on Unreal Engine 4.
I've tried putting them into UE4 SDK but I'm not very sure if i identified these maps right at all.
http://store.steampowered.com/app/298900/

Now here are the maps
These both end in the suffix of _RGBa 
I've marked them with their respective channels.
Metalness(???)

Roughness(???)

AO


And a seperate map ending in the same suffix.

Eric Chadwick

Metalness is usually just white and black. But it depends on the look they were trying to achieve. Do you have any screenshots from in-game of this particular model? 

Last map could be for team colors, or for physics response (different particles & sounds when struck), or some other effect. Usually vertex colors are better for solid colors like this (less memory overhead), but you never know...

Valandar

B looks like an AO map... R could be for roughness... G? Not sure. If they use vertex colors and use the separate map, could be a shading detail over the vertex colors from the separate map? I dunno? Maybe specular strength?