I'm trying to figure out how to tighten the handle on the front door of a new condo unit. I've done a bunch of googling and watched some YouTube videos, but they all either have 1) visible screws, 2) a hole that you can press a pin or hex key into, or 3) are Kwikset handles that you twist and pull. It appears that my handle doesn't fit into any of these groups, as it has no visible screws, no holes that I can see, and is not a Kwikset handle. Some photos are below. In the 3rd photo, I took off a plate, which is why the screws are missing.
Inside (Left):
Inside (Right):
Between inside and outside:
Outside closeup:
Inside closeup:
Outside handle closeup: