Agreed, but that's sort of what a primary is all about.
The candidates all need to put their best foot forward and make the sale to the voters. That includes getting all the facts of their negatives out in the open, and to let the voters decide whether those negatives are true/false, or whether they're deal-breakers or not.
I think Sarah's got what it takes to have that conversation with the voters, and I also think that once voters have all of the facts about what caused her to resign, they'll see that she did the right thing for the people of her state.
You are absolutely right. That is what a primary is all about.