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You can check the data yourself. I browsed through all the major auto manufacturers and besides Tesla, I couldn't find one with 5 stars across the board. Most manufacturers had at least 4 stars or greater in every category.
edit: a little confusing, but Overall 5 star does not mean they scored 5 stars across the board. They test Frontal, Side and Rollover. You can get 4 stars in one or more of those categories yet still get a 5 star overall rating.