Answered by Sayyidi Habib Umar bin Hafiz (may Allah protect him and benefit us by him)
Can we attend gatherings in which forbidden musical instruments are used?
If there is scholarly consensus that they are forbidden then there is no way we can attend. If the scholars differ over whether they are permissible or not, we should assess what benefit there is in attending. If there is a great benefit to be had in attending, we can overlook the fact that the scholars differ over the permissibility of these instruments. If there is no great benefit to be had, it is better not to attend.