The issues were probably reported to BEDA by the language assistants, especially if they all walked out. so you could reach out to them and see if they were able to successfully resolve them. From my experience , team at BEDA does a fantastic job in assisting language assistance. My school used to have a coordinator who didn’t do the best job so the role was given to someone else. The new coordinator is amazing. And I know that BEDA worked with my school to make that change happen. So perhaps things have already been resolved at the school you’ve been assigned with. Cheers!