John there's no expiration on the CFO sticker.
(The only restriction is that the destination should match ticketing - In which case the CFO will quite happily issue a new one, at a fee of course)
I'm not 100% sure about the Registration Certificate but I think that's also no expiration
Make sure to double check the details on both the sticker and the certificate if everything is correct.
Do bear in mind John that there are other time constraints involved. That CFO sticker cannot be secured until the visa is valid.
The visa will issued for 33 months validity and if she does not arrive with the first 3 months she'll end up out of visa sync and will have to pay for an extra one. (not cheap and generally an unwanted pain)
Also the TB testing certificate is only usually valid for 6 months from date of issue.
Why is NBI clearance needed?