There are slight differences on Sofia as well. With the lighting, there's a little more light on her in the second render, as expected. You can also see little grains appearing, from missing the denoiser basically.
I do agree that it would definitely not be worth 2 hours for just those differences. The floor does look a lot better in the second image, but who really cares about the floor?
I am curious what % of quality you have on the each of the renders. When I render I usually select the percentage, not the number of renders (I put a hard cap on 5-10k depending what I'm rendering).
I want to mention that most of the render time comes from 2 things. A lot of geometry and complex lighting.
If you have a simple scene, lit from a hdri mostly, with 1 or 2 models at level 2 or 3 details, it should not take more than 5-10 minutes, even for 95-96%.
If you have a scene in a dark room, lit from different sources of light, bounced around reflective surfaces , you can even have it without people and it will take a long time. Maybe a few hours and it still wouldn't look completely right.