I think the “intent” to violate the rule is only meant to mean that it is understood that in the normal interaction between robots there will possibly be some destruction, damage, tipping over, or Entanglement caused to one robot by another, therefore it becomes a question of whether, in the referee’s judgement, that damage, etc. was intentional. A robot driven in a way that intends to violate G12, but is unsuccessful, would not be in violation as it only becomes in violation is there actually destruction, damage, tipping over, or Entanglement. See the bold type in the full quote of the rule below. As a referee, if I saw a robot attempting to cause destruction, damage, tipping over, or Entanglement, but was not successful, I would certainly pull that team aside after their match and let them know that continuing to attempt that strategy may certainly be grounds for disqualification, particularly if they succeed. Severe violations, in my opinion as an event partner, may be grounds for disqualification from the event.
Is a rule violated if the attempt to violate the rule is unsuccessful? To me, this is more of an ethical question.
As I mentioned in my post, as a referee, if I saw a robot (unsuccessfully) attempt to violate G12, I certainly would pull them aside after the match and give them a warning that to continue to do so could and most likely would result in a DQ.