I am confused. Are you saying you have three different computers including the main computer? You are taking a backup of the main computer and restoring them to the new computers all with SQL installed?
You are then using the two new computers to connect to the main computer? How would that give you redundancy? You may have equal computers at the beginning but you will be reading and writing data to SQL on the main computer. None of the data on the new computers would be affected (I hope). Therefore, you would not have any redundancy after the first day; the first note even.
Each computer cannot save and receive data to and from but one SQL server. You can only have one AC instance.
