Welcome to YT!
How wonderful of you to have been rescuing for 43 years! Thats amazing!! Inspires me to get a rescue next time we decide to have an addition to the family!
I don't have experience with deaf yorkies/dogs, so not much help here! I hope someone replies who has experience with this!
I don't think their hair in their ears have anything to do with it. It sounds more of a birth issue or a accidental issue.
As we all know when one of your senses is down, you get more sharp on your other senses like your sight, smell and touch. So you will have to accomodate and make use of that.
Please keep us updated and share pics too, we love pics here