When Ruby leaves Rogers art studio and walks to Detective Killian' car it is late afternoon, her shadow as she walks across the street is long. Ruby suggest they get something to eat and Jake suggests a diner he knows. But when they arrive it is night, and there the diner is not crowded, suggesting it is late after the dinner rush, perhaps 3 to 4 hours after they left Roger's studio.
Derek Saylor (Mig Macario) the hotel manager and friend of Ruby in Silent Witness (2019). He needed to wear glasses in that movie. In this movie he does not wear glasses and no mention of hotel job.
14.20 - Derek Saylor places his untouched smoothie on the side then after he's left and Ruby turns to talk to Amanda, Derek's smoothie is no longer there.
The two combinations for the housekeeper's safe do not contain the same digits. The first option is the address, 3-1-2-1. The one that works is the year she started her business: 2-0-1-3. The 'zero' is not one of the keys that had been recently touched, as indicated by the 'fingerprint' trick.
The murderer had no way of knowing for sure that the car would crash. Too many possibilities that it might not work. This murder happen by shear luck.
Towards the end of the movie, Ruby and her assistant are seen from behind walking alone on a paved path/road surrounded by woods. When seen from the front they are on a gravel path, in a park with people and dogs around,