I am a US citizen applying for green card for my mom. Already applied for I-130 and now preparing to apply for I-485.

1) I have only NABC for my mom. Since NABC does not have exact date of birth, should it be accompanied by affidavits saying that someone older know her as born on that date?

2) My mom's names are misspelled on various documents - mom's NABC, mom's high school certificate, my birth certificate.
How can i explain that all of these names belong to my mom?

3) If affidavits are required from both questions # 1 and # 2 above then can i get one set of affidavits for both purposes? how many are required and who are best people to provide these affidavits - mom's brothers or sisters?