Marks on display after separating glass
I have a question for people with more experience in LCD separation. Look at the picture in the second link below - there are several marks on a display of an iPhone 6 I have not encountered before, red line and dark spot.
The display was broken after a fall. Here is a picture before separation:
And here is a picture after separation:
There were none of those marks before glass separation so I am wondering if this could happen because of an unprofessional separation or is it possible that it just somehow was not visible before (with glass on a display)?
According to the technician words, the dark spot on the bottom right side marks a place when the display is a bit bent - which was not visible with the glass glued on top of the display.
Thank you in advance