The question I have is did the company follow progressive discipline?
If they didn't give a written warning before the suspension, then these, or any further discipline could be thrown out.
I believe the idea as treating each as a separate 1 day suspension goes along the lines of progressive discipline for each type of infraction. If the company tried to lump the two together under failure to follow instructions, then dicipline could progress further towards termination. I'll have to double check the language, but it is my understanding that the company has to do progressive discipline for each different infraction. So, your buddy would have to have multiple no scans, or multiple failure to fold in mirrors, in order to move to the next level of discipline.
I think the BA was right, assuming the company actually followed progressive discipline in order to get to suspension. If they didn't, then these should be written warnings.
Progressive Discipline steps should be outlined in the regional supplement under grievance procedures/machinery.