Beer in BBQ sauce

It all happen Sunday morning when my family and I went for breakfast which we often do . I order and when the food arrived i attended to my son who is 2 years old . We always sort my kids out first so my wife and i can then eat . My son was already half way through his meal when i decided to have some of the BBQ sauce which was on the table and after adding the sauce to his plate while eating he started to crying and spitting out the food off his mouth. I then got afraid and i tasted the sauce it tasted like beer. I approached the manager and he informed me that the sauce was in the sun and it might be spoilt . I asked him what is the process for checking these items or to ensure these sauce is always safe for us to consume , he could not give me an answer , The next day i took a day off from work to take my son to the GP because he now has lose stools . I was contacted by two managers to taste the sauce which they refuse to do . This is really unprofessional for Senior Managers to make assumptions without facts.