It was the elders of his congregation that stopped by, most likely the ones who disfellowshipped him. Apparently he has expressed that he wants to return without you knowing, but it's only because of his family.
If he's "trying to come back" to JW's, then he will either ask you to marry him (and it would have to be relatively quick) or break up with you. They will give him an ultimatum.
SIDENOTE: You don't have to become a witness for him to marry you and you don't have to attend any meeting with him. That's only if you want to.