I think the safehand sleeve basically rules out most instruments that require two hands. I’d say piano and other keyboard instruments are off the table. It would be too restrictive trying to play big chords or make large jumps. And it would most definitely get in the way of scale runs or arpeggios. A glove might work, depending on how flexible it is. I’ve tried playing piano with gloves on before, just to see if I could, and it was manageable. However, as people have said above, I don’t know if the use of the left hand would even be socially acceptable in Vorin culture.
As for strings, if played left-handed it might work with a glove, but the bowing hand needs to be very flexible as well, so again, the gloves would have to be non-restrictive.
Maybe there are some in-world instruments we don’t know about too?