Welcome to the forum. It's good to read the posts from breeders that appear here, because all your suggestions and information is welcome to all of us non-breeders.
My heart breaks reading your wonderful story of Dinah - it is so clear she is a huge part of your heart -you will have such wonderful memories of her when it is her time to give up the pain. I also do not believe dogs don't have souls - of course they do - the unconditional love they give, the way they try to help when you are emotionally suffering, the joy they get when they see you coming after a separation - all these and more are proof they are very soulful. A loving companion dog is God's gift. All our hearts are with you, and our tears flow with yours. God bless.
Welcome to the forum Ty and Luna.
There is nothing i can add that hasn't already been said but you have certaily come to the right place for help, information and friendship.
It would be lovely to see a pic of Luna and your two cats.
Hope you get Luna sorted out quickly.