Something similar, many, many years ago. Back in the '70's when I was in my 20's. I was at at an assembly in Ft. Worth, TX. My friend was with me, he was kind of a "goof". Well, so was I actually.
Anyway, my friend came into the auditorium late, everyone was already singing the opening song. I think it was song number 65 or something like that. My friend says, "What song are we singing?"
My friend did not have a good singing voice. In fact, it was terrible, and he sang LOUD!
So, I started to tell him we were singing song number 65 when, all of a sudden, a voice in my head told me to tell him we were singing song number 66. It's on the very next page! Open the song book and you could see both songs.
So he begins singing, very loudly, the words to the wrong song! He was doing his darndest to make the words fit! It took every bit of effort that was within me to keep from laughing out loud! I was trying to keep the tears in my eyes!
By the time he realized what I had done the singing was over. He laughed, though. Then he threatened to kill me. Oh, if only I had a video of that moment in time!!!