Served Alcohol At Work When I Thought It Was A Non Alcoholic Beverage. Terminated For Policy Violation. Oregon.

On Saturday I was at the end of my shift (security lead in a grocery store) walking to the punch out clock when a vendor doing a tasting in our produce department asked me if I wanted to try something before I left. The only tasting I’ve seen done at this store was for non-alcoholic beer and wine and assumed this was the same. The vendors are also supposed to be trained to not to serve alcohol to employees. I took a sip of the glass that was offered to me, realized it had alcohol, set it back down on the table and went to go clock out. I was confronted by someone from my department who asked if the beverage was alcohol, to which I responded that I didn’t think it was until I had tried it. I didn’t hear anything else about it until today when I was terminated for a drug and alcohol policy violation. I maintained that I did not KNOWINGLY consume alcohol, they didn’t want to hear it. I also have a paid leave coming up January first, it may have something to do with it but I don’t think I can substantiate that. Is this worth bringing to an employment lawyer?