Implemented this year, but with mass confusion as their handbook didn't state it and the vtac guide said BOTH. Latrobe website only update it's "OR" to a "BOTH" halfway through the year apparently.
My thoughts are that they were unable to implement the both requirement. If you start year 12 wanting to do Dentistry but have no awareness of the pre-req, you shouldn't be adversely affected by their failure to properly notify you of the changes.
Therefore even if they said - oh sorry - you would possibly have even legal grounds to challenge them and effectively enforce your place now that you have been given it.
But pretty much, my guess is that they realised their mistake and have subsequently made it an OR requirement for this year due to the issue.
You should ring them up anonymously as suggested. You should not act unaware though - I'd say that would make you out as dishonest and potentially may result in a situation further in the year where you could literally be in trouble.
But I'd suggest that because of the confusion this is a grey area. But really it seems objectively they have failed to implement their own pre-reqs due to their failure to notify you.