https://nafme.org/wp-content/uploads/2023/08/Copyright-Guidance-for-Performance-2023.pdf

"Unless the appropriate licenses are obtained, recordings should not be posted on publicly accessible websites (e.g., YouTube), but limited to password-protected school resources which conform to the TEACH Act"

So I think you're fine since the BAND app is not public. If you paid arrangement rights, then you'll be fine.