Just to add, it's interesting to me to compare this case with the murder of the Dermonds in Georgia. An older, wealthy couple, targeted for an unknown motive, very unusual actions by the killer(s).
The Sheriff in that case has spoken innumerable times to the media, providing lots of details (too many details to accurately remember) about the results of the investigations.
However, beyond providing lots of content for the true crime industry...it remains unsolved over 10 years later.
So, IMO, whether police provide the public with details or don't, doesn't affect whether they solve the crime. It only affects the number of true crime channels that will make an episode out of the case, or the number of times that 'new details' gives the media a reason to rehash the basics of the case.
IMO police in Canada prefer that their suspects don't know anything about what police know. When you're playing poker, you don't show your hand.
JMO