That last point is very important. Whilst the dog's owner/minder is responsible for having pets under control on the public highway, the owner/driver of a vehicle is responsible for always maintaining a speed, distance and visibility ensuring the safety of others. The dog-walker had the other two dogs on leads. The one which was crossing the road was presumably considered sufficiently safe and well-trained (most dogs are!) to cross "on command" when it was safe to do so.
Having frequently witnessed - as both a driver and pedestrian - pedestrians having to run the last few feet, or even the second part of the road, to get from under the wheels of impatient drivers I would caution that "there are two sides to every story".
An anecdote. A friend's daugher took her driving-test a few weeks ago. She failed. During the test, as she approached a pedestrian crossing in a 30-mile-an-hour built-up residential area an older adult in a mobility-scooter was coming towards her, on the pavement. As he had not actually REACHED the pedestrian crossing and there was no indication he wanted to cross she did not slow or stop but drove across the crossing, then saw in her rear-view mirror that the old man had, in fact, crossed at the crossing.
The Examiner had also noticed. The "fail" was on the grounds that she was not driving sufficiently defensively to avoid a possibly serious accident, since the mobility-scooter was adjacent to the crossing which was sloped to facilitate pushchairs and wheelchairs. Note......."adjacent".