As he is a representative of the company he is employed... I would send the photo along with a letter/email to the owner of the company and the HR department. Since he is working, evidently, he has been medically cleared for employment if not them he would not be in a business owned vehicle... Include the fact the person at the gas pumps stated that he does this regularly.... The owner could get the video tapes of the issue.... if needed.

by blocking the pumps and parking illegally he is bring a disgrace upon his company... Would the boss be upset, oh yes.... Because it is a disgrace to HIS business.... Go get him