I think he is adorable , also hernias seem to be common and if they are getting it fixed , fine.
Is he their dog or are they breeders ? If he is their dog what is their reason for rehoming him.
I have 2 yorkies and think they are great company for each other.

How old is Tink ? I got Lottie when Alfie was about 18 months old and they did great with each other.