This is a comment by Outerarm on the steam discussion board that I found very helpful.
https://steamcommunity.com/app/1397920/discussions/0/3169946..."Use a combination of Rare or Legendary level scientists, Books of Success and tickets. I managed to get to L50 with a Warped Book of Success (+3%) and a Legendary scientist and skipped all non-green excavations to ensure success (green excavations are 0% to 5% death chance, Legendary status takes this to 2.5% rate, and the +3% from the Book of Success take it to -0.5%, thus making it impossible to die) . I used up all my ~190 tickets I'd collected, but managed to get there in the end.
Not long after I found 3 more Books of Success in rapid succession so now have a +9% on excavation success. My Legendary scientist is now at L100, and I have a Rare scientist at L64."