How do I cut-out people in this shot but then also show the background

any way of erasing the small outline and leaving the background behind the people?

There is no way to "leave the background," because the background does not exist in the file directly behind the figures. The only way to get the result you want is to carefully rebuild the background in small sections. The clone tool can be of help with this, but for a background this complex, no fully automated method will do a good job of this.