>>150208402
I saved some scrapped storyboards from the final episode that showed what you are describing.
It was Luz giving her speech to Collector about how you need to understand people in order to be their friend, and he responds by asking her if she would attempt that with Phillip. She responds just by grimacing, he then points out the hypocrisy, and she has a moment of realization.
It showed how Luz understood that Belos was still a person, but also that Collector was intelligent/perceptive enough to question the premise of Luz's explanation and that despite how horribly Belos had treated him, Collector still felt bad for the person who he'd spent 400 years with.