What I would have said in a nice, respectful tone...

Ma'm
Some people are afried of dog's, and while I'm sure your sweet darling Maya wouldn't hurt anyone, I know it might scare some people to have a dog running loose, it is also company policy that all dog's are under compltle controlle (if it is company policy). I know your baby is probly a sweet heart, but could you please re-gain controlle of her?

She, most likly, will say "Sure"

and then I would say

"Thank you, she really is a wonderful dog!"

And walk away.

Ash