I would use the brick light for the fire element, and then have an over head light gel-ed to the same color and mask it so it created a small circle of light around the fire, then I would use a fain blue light as fill for the surrounding areas.

If you wrap a piece of aluminum foil (or black wrap) around a lamp and place it directly above the bonfire, making a funnel with a hole on the end, you can use that to limit the light to essentially a small, soft spotlight over the bonfire.

Well, an orange light brick is not very bright, so that's a bit of a problem.

Perhaps you should still have a light built into the set, but you should do a brighter one.  Do you have any?
Of course, a brighter light may be bigger, and may involve having to elevate the entire set significantly to get it working.  If the light is still too dim you could crank up the exposure a bunch.  I often use really long exposures, of course, most people don't have the patience for that.

I still think you should have a second light source, though.  As well as the fire, it would bit nice to have a subtle bluish white glowing coming from above, maybe slightly behind.  It should be very dim compared to the fire, though.  So dim that without the fire it would only add a faint shine at the edges of the characters.  But I still think it would do well to enhance the scene.