
Aging often brigns changes that cause a dog to loose confidence,amd an overattachement can becoem ful blown seperation anxiety, which I would say is classicly being exhibited by the dog.
In less extreme cases dogs that used to be bomb proof due to diminishing hearing and or dight start to be afraid of things that didn't worry them, cush as thunder etc.
Sadly I would say that if soemoen cannot be with the dog during the day, and they cannot pay for day care the dog might have to be put to sleep to sve furthr suffering, as it is definately suffering for prolonged periods basedon the video evidence.
There are drugs that can be given that can be helpful if the dog has the cognitive problem, but it may ony be a temporary solution.