talking about sneak attack rules I've heard this hypothesis.
the Vivisectionist says At 1st level, "a vivisectionist gains the sneak attack ability as a rogue of the same level. If a character already has sneak attack from another class, the levels from the classes that grant sneak attack stack to determine the effective rogue level for the sneak attack’s extra damage dice (so an alchemist 1/rogue 1 has a +1d6 sneak attack like a 2nd-level rogue, an alchemist 2/rogue 1 has a +2d6 sneak attack like a 3rd-level rogue, and so on)"
according to several players one level is enough one level from Vivisectionist is enough to make nature fang druid have a complete sneak attack (example 6d6 at level 11, one level vivisectinist and ten level nature fang druid).
or how do I think it works, based on what is written does it add only the single vivizesionist level, having only 2d6 sneak attacks at level 11?