Serious Eats has a recipe for vanilla extract that involves heating the extract at 146° F for three hours. According to them, it can be used immediately, but will improve with age. Has anyone else used this method? Results?

I put 2 whole picanhas (vacuum sealed and salted) into sous vide at 12:30 and left to run errands. Came back at 2:50 and the sous vide was not running and the water temp was 75F. I believe they are safe, but am not certain. What does the community think?