I found that Magix AVC/AAC render some videos with low light very bad in Vegas Pro 15. When I use Sony AVC/MVC in VP15 or Main Concept AVC/AAC in Movie studio 13 it´s not at all that bad. Look at the brown porch in left bottom corner.
Original file
Magix AVC/AAC 
Sony AVC/MVC in VP15
Main Concept AVC/AAC in MS 13
Edit: All files actually look even a bit worse after uploading to this post.
Link to video files: https://www.dropbox.com/sh/j8hjzjxttnfn7uo/AACNLjU1HPVDvBsUiqxdOdJta?dl=0