Hans Hubler, I think he was involved in a major row when serving where the need was greater in New Caledonia. I think it was half discussed in a YB report. Unpleasant business
Rex Manwaring - one of those people who seem simple but may be really complex. Another XJW knew him quite well, and tells this story.
When RM was a special pioneer, he was assigned to a town that was really tough to witness in. Simply no-one had interest (Quite a few towns like that in country areas). And RM told my friend he was getting so down-hearted, nearly always working alone, and never being able to discuss the Bible, that when one morning, the next house was the Catholic Presbytery, he decided to knock on that door** too. The priest came to the door, and invited him in and RM spent the morning there, explaining to my friend that nothing came of it, but it allowed him a chance to talk about the bible.
** What do you guys remember? I have the impression that generally, most JWs bypassed the homes of clergy.