Here is how I would have rescued Anne Frank, family and friends

Do you remember the canal in front of the House and business where Anne, family and friends were hidden? It was very busy, with a lot of store supplies and transportation was done on this waterway. Being a retired captain, if I was a time traveler, I would go back and be about 30 in 1943, and commander a covered sea going boat like that one on the right above. I would use a supply boat that is seen in that area regularly. I would have the owner, deliver supplies then have a fake accident, that would have him hospitalized. And I would remain hidden on boat until late at night on a foggy evening, and on a signal, the Frank family and friends would come out steathely and hide aboard out of site. I would use the tide and a large oar, keeping the engine silent, and no lights, until I got away from civilization. Then I would turn on the engine and head out for England for our safety. The owner, when out of the hospital, would claim it was stolen. He would have been recompensed royally a few days beforehand. 
P. S. My favorite sailboat of all time was a stout wooden sailboat built in England.
So tragic, that all this happened a long time after D day and Holland was one of the last, if not the last country liberated from the Nazis. Even Belgium, where her bf "Hello" and family escaped to liberated a year before. Then most of the deaths of the Franks occurred in 1945 just 2 or 3 weeks before liberation. 

Anne with her beloved Father enlarged photo of her in Anne Frank Museum.