Hello there,
I have checked the sample file, when i open it i can see the empty placeholders instead of images, and a message inside that says that you may not have enough memory to open the images or the files might be corrupted. If you have a backed up original copy, maybe try that. Or we can figure out a solution to this issue. Would it be possible for you to send me the complete file and let me know which version of excel you have used to save it in.
Update
The images have started to load up now, can you please confirm what error your customer is getting in place of the images? that would be helpful to figure out why he is unable to view the images.