Sorry you had to say goodbye
But you certainly did the right thing... from the info. provided it appears only the rightful owner could have known the information they provided... if the dog did not seem happy to see them it could be that the dog is not treated well, or something else entirely, it would really only be speculation and you cant keep someone else's pet on speculation alone.
I will say again though, that good things will come to you for taking in and caring for this dog as your own for the last few weeks... when you have a new baby that is all yours, I cant wait to hear about him/her!
