I think human-human dynamics are so complex that you probably did the absolute right thing in that situation at that time with that person.
I mean even using up 1000 words it is just impossible to give all the details, who this guy is to your family, how often he is likely to visit, what he was probably thinking, and so on and so forth. Sometimes it just doesn't make sense to say or do anything, save protect the pup, which is what you did.
You protected the dog, didn't alienate anyone, did not scare the dog in the process, did not upset your husband, etc. It sounds like you did enough and not too much, in my opinion.
Bear Cub, Hepsi-Pepsi
Cujo2, Karma Chameleon
Ramona the Pest, Kojak -- who loves you baby?
Tiny Tinnie, Susie's Uzzi, Kaiah -- The Baby Monster.