If you want to "anonymously" get that information, call and nicely ask stating day and time you were there "I was given such great service by a supervisor there on ___ around ___ o'clock and did not look at the the nametag, but they had a supervisor shirt on. Could you help me narrow down who it could have been so I can mention them in a review?"
Who knows! What time, what day, supervisor of fries or supervisor of milkshakes?
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