I didn’t think she massacred the song.
Maybe your feed is off?
She did a great job on a song that is NOT easy to sing, especially a cappella.
It’s difficult to sing, true. She picked a good key for her range. And she kept pitch from beginning to end, a capella. BUT ... so many of them, when they get to “free” at the end, they think it’s cute to screech up a fifth to show off. Just sing the song as written. (But that’s just me.)