That does sound a nightmare. Having been an executor for my aunt's estate, I appreciate everything you say. She was in England too, so I used her solicitor for all the legal stuff. She thought she had everything well organised but it was shambolic, as in her last year all order had gone.
So we too are trying to get everything together and clarified, all in one place, so executors can lay their hands on it straight away. All savings/bank account details, insurance, the password to our computer is important too for stuff not printed off.
We have no pets left which is a relief in a way (both our terriers died recently, and we've not had a cat for 6 years). The livestock is more of a problem - too important to go to a sale, but our executors are not interested. The possibility of both dying within a month of eachother is more common now with the Virus, so definitely need a plan B!