A small amount of vaseline ingested won't hurtthe rabbit, but I wouldn't want any of my rabbits ingesting too much ofit. Definitely wouldn't look to it to help pass fur.
Sometimes I'll put it on Fauna's bottom, but very sparingly. I know she can't really clean herself.
If she was in a molt, personally, I'd not get vaseline anywhere nearher. It's sticky and thick. Not a good combination if run up against aball full of fur.
-Carolyn