She's quoted in one story on-line as saying she attributed her longevity to good genes and eating two raw eggs per day.

She could well have been right.   Eggs are the perfect food and if not overcooked (the yolk needs to be runny -- or raw, essentially), they are a great source of both active forms of vitamin B12.   Both forms are crucial to achieve longevity.   The other vitamin she must have got from eggs and eating other grass-fed animal proteins is vitamin K2, without which she would have had problems with fragile bones and artheriosclerosis.   

Interestingly, most North Americans are deficient in vitamin K2, and so we have lost of osteoporosis and heart problems.    Vitamin B12 deficiency (particularly adenosylcobalamin) is a major issue worldwide, especially for vegetarians and vegans.

She probably had a very good basic metabolism (based on genetics) and a source of very nutritious eggs from a farm or someone who raised chickens on a varied diet.