My vet feels very strongly that both my seniors were hit.

They are very afraid of an open hand coming at them. After 9 yrs. I still have to be very careful how I bring my hand down to pet them or pick them up.

There are
everlasting consequences to hitting/slapping/beating. My 11 yr. and 10 yr. old still have occasional accidents. If that is going to be a problem for you in the next 15/16 yrs. I suggest you re-home your darling Yorkie. (Or get professioanl help as has been suggested.)
Joanne