These conversations happened in the clear. It was well known and disclosed at the time of the investigations that this judge (and a few others) were exchanging information about the case with prosecutors and defenders.

Also, "tips for new avenues of investigation" may be ethically questionable (although it's hard to make the case for that), it's not crime at all. It would be crime if the judge was taking sides in the ruling, which that specific judge is not accused of.