Hello General Mumble,
I just ran a test on my end to check and see if this was a bug in a new blank project within the 4.9.2 engine version. All you should have to do in your case is to disable ‘Fog’ within the General ShowFlags of the Scene Capture 2D actor. Below are some screenshots of the setup I used.
Render Target with Fog Enabled
Render Target with Fog Disabled
Let me know if you have further questions or need additional assistance.
Cheers,