Thank you very much for these instructions @diarra and @Maryn ! 
I can also confirm everything that @Maryn added for the image 2.4.1 (stable)! For me it started with the script not wrongfully claiming that the phone is still locked, but simply not flashing the images and getting stuck.
I did not yet try relocking the bootloader but up to the “edit”, I can confirm that I had to do every additional step as well!
(btw.: the “more colorful” recovery is the one from /e/ which you flashed just before with the script! It says “e” and also has the reference to the version 2.4 in the upper corner 
)
PS, I told my mom that getting /e/ on the phone would take me 30 mins. It was 5.5 hours now 
(But I would have nothing on there if not for this forum 
)