That is the bit that bothers me - what are they saying about the professionalism of interpreting services? I've had similar objections raised regards amenuensis (verbal to written transcribing services for blind students) because they think for some reason you will help them with it. Why would I? My professional job role and engagement is to write down what the person says, no matter if they are wrong answers. It is an undermining of sign and interpreter services as being a professional engagement to do a given service, like a Spanish interpreter can be relied upon to read out the script but oh no, the ASL interpreter cannot be trusted and will be giving you all the answers.
Different languages have different structures, look up one word in an English-French dictionary and the same word might be translated in 5 different ways according to context. Similarly with ASL because it is a different
language. When someone is not a fully native speaker of a language there are subtleties which aren't quite equivalent, like in French the "we" in a sentence like "At Christmas we eat turkey" would be replaced with "on mange" or "one eats", and it facilitates understanding that it is a "general we" rather than a more specific "we" comprising the speaker and a given group of people she expects to eat with. It's a correct translation but it's not
quite understood in the same way, and that's with a very simple sentence of text, how much more complex when these things are built upon. If native speakers of other languages are allowed translated material I don't think ASL should be disallowed, it's services for everyone or services for no-one, but particularly I think the comment that the interpreter can't be allowed in case they help with the exam is outrageous and should be challenged.