Maybe I am not fully understanding, All I see is a much slower additive/dissolve transition from what I normally use. I did fade into black allot during that scene, but believe it or not, in renpy, to do that, it has to transition to a black image. My most used transition timing in most cases is 1 second for most the game, but for sequences like that, I transition in 0.06 and 0.04 timing between stills and then 0.1 and 0.5 when fading to black.
On patreon, the voting ended with like 75% loved it and want more of it, the other 25% was more or less its cool, but is it worth the effort. It took about 50 hours to do that scene, so for your average person that's a week of work, but at the rate I work when I am really focused on something, it was 3 days.