I particularly like the eyes of a different hue and titian hair augurs.
The first two are very specific. Unatural aging? Is that likely to happen in any given character's lifespan?
Glad you liked them.
As for your question . . .
I believe Jewels of the Carnifax has an "aging-gas" trap in it that magically ages characters who run afoul of it. So yeah, it can happen. There are also a couple of older D&D modules that feature aging issues, for those who convert them to DCC RPG. I'll admit it's not the most common problem in the world for characters to run into though.
As for Born under the caul - drowning/asphyxiation has been deadly in pretty much every iteration of D&D. That particular augur was inspired by the Lizardman monster entry and how they can submerge and drown characters they attack. I remembered the folklore about sailors purchasing cauls to protect them from drowning. (For some reason it just came to mind when I read the Lizardman entry, and it sparked the idea for the augur, which in turn led to the entire list I created.)
Hope you get some use out of them!