AITA for arguing that Jimin from BTS did not sing the famous "Seňorita" against my mom?

So this morning my mom (50 F) showed me a fan-made video of the famous song "Seňorita" but with footage of Jimin from BTS edited onto it to make it look like it was an official music video ( the video had 6 million or so views). She made it sound like Jimin was singing the song ("Would you expect to hear that voice from this man?" she told me).

I (18 F) pointed out that this was a fan made video, but she insisted that Jimin was actually singing. Then she showed me another video of him singing one of his actual parts. I told her this didn't prove anything. Then she showed me another video that was titled something like "How would Korean singers sing Seňorita" or something similar. It was a bunch of pictures of famous Korean singers, and whenever a certain part would come up the picture would change accordingly to make it seem like the person in that picture was singing. Another fan made video.

I also pointed this out, and she got pretty upset although she was not angry. I made her pretty sad. She was excited to share this thing she liked with me and I feel like I've ruined it for her. Maybe I could have played along and acted as if what she believed was true? I don't know, since that feels like lying. Should I have played along instead of insisting on the truth? Am I the asshole for making her sad because I insisted on the truth? Maybe I should've let her have it, y'know.