Can't add unfiltered_html to custom user role

I’ve created a new user role in our WordPress theme and our users need to be able to embed YouTube Videos. I tried adding ‘unfiltered_html’ => true to our add_role array but it’s not working. I’ve done some googling and I’m thinking that doesn’t work because we’re working in a network (multisite) environment. Is that correct? Is there another way to give them this capability?