Looking with a loupe on a light table I can’t for the life of me see the lines
Thanks for posting those; your processing looks A-OK! No worries there.
I see no weird lines either, but at this size they may not be easily visible. Also, if you're looking for them with a loupe, these will be very, very faint and very hard to see.
In the other scan/photo, they do show up alright:
I assume you photographed the ones in #28 with your smartphone, right?
What do you get when you try to photograph the negative with your 'scanning' camera using the sun as a light source? Use a sheet of diffuser material like milky plexiglass or even thin tracing paper and a spacer between that and the film. I am beginning to suspect we're seeing an interference between LED flicker (PWM) and some aspect of the capture timing in the camera. What kind of light source are you using for 'scanning'?
Mind you, I'm aware that you also got the strips on a Noritsu scan; I still can't explain that bit.