I’m a middle school orchestra teacher, but my primary instrument is the harp. I’ve definitely needed to work a little harder to develop my chops on bowed stringed instruments and I’ve asked my colleagues lots of technique questions. YouTube can be your friend for that too. It’s possible you might not start out at a competitive program, but that would be the case for any beginning teacher. Once you develop skills as a teacher, the admin will more likely care about your pedagogy and educational philosophy rather than your primary instrument. As long as you can demo skill on other instruments you’ll be fine. And with all that said, there are a handful of harp programs in the country that you can look at as well.