Wrongly accused of being drunk

My husband is a uber eats driver. He had to do a pick up from pick n pay beacon bay East London. When he got there he couldn't find the package asked for help. The security then told him he must not get there drunk!!! He does not even drink any alcohol. The manager then admitted he was also guilty in that matter. When we insisted on them doing a breathelizer test they refused. Accusing an innocent person from the security is not on. So many people complain about that store. What is pick n pay going to do about accusing my husband of arriving there drunk and gave the package to another driver instead. I'm very upset about it. We feel like taking this matter further