I think he's adorable. And that you are great. I'm no expert but he looks like he for sure is a Yorkie, his coloring is about right for that, and he looks all terrier to me. 8 1/2 pounds is just over the range for "standard" yorkie. And... to ME it looks like a little bit of mini schnauzer thrown in
or silky. Again, no expert here - but you appear to have found and saved (thank you) a wonderful yorkie boy!