La Fenice employees have been getting death threats since the storied Venice opera house said it was cutting off ties with Beatrice Venezi, the young conductor who was set to become its musical director in October, the RSU union representing them said on Tuesday.     The opera house's orchestra and staff had been protesting against Venezi's controversial appointment since it was announced last year, complaining of alleged political interference due to her alleged ties to Premier Giorgia Meloni.