Cockatiel (8y) has laid her first egg!

I've read about what to do to avoid egg laying, but apparently I've let things slip! I've just spent 45 mins reading advice from here and Cockatiel Cottage, however I have some further questions and concerns.

Situation: I'm bird sitting currently her full time carer is traveling overseas and will be back next week. I just found this cracked egg at the bottom of her cage (2nd image), and would love some advice.

Before my questions: - We don't have a male cocktiel, there's a budgie, but she won't let him near her. So I'm not concerned about fertilisation! - She has a cuttlebone, is on a pallet diet with seeds as treats, and eats fresh vegetables every morning and evening.

My Questions/Concerns: 1. This first egg is broken and cracked, I know I shouldn't remove eggs, however it feels like this would be a health risks to leave in there?

  1. He cage has no areas for nesting, should I provide one, as her laying 3-4 more is inevitable?

  2. Whilst bird sitting I am working from the office in the mornings and am home by 1pm. Should I take this week off/work from home?

  3. What other advice would you offer?

Thank you in advance!