US Immigration from Philippines

Hello everyone,

It's been a while since I've been here and my googling and searching skills in regards to immigration and stuff related to it became rusty. Sorry if this had been asked please copy and paste the link for the topic so I can look through it. Here's the scenario.

Ex sister-in-law is currently 17 y.o will be 18 this December. Her father is a US Citizen so therefore she is already a US Citizen thru Section 322 of the INA. But the father is dead and they do not know where they're father's Naturalization certificate is. I do have a copy though from when I arrange the papers of my ex mom-in-law I was able to save a copy. What does she need to do? I feel bad that I can't be of more help to her. Her older siblings just don't bother trying to fix what she needs. I would really appreciate any help. Thank you.

https://www.gmanetwork.com/news/news/nation/749553/duterte-places-ncr-nearby-areas-back-to-mecq-beginning-monday-august-3-2020/story/

My wife thinks this means there will be no transportation and therefore she cant go to an interview at the embassy.

2 Judges struck down Trumps public charge ruling. They said you cant ask immigrants those questions during a pandemic. It applies nationwide.

https://www.npr.org/2020/07/31/897429845/twin-rulings-by-federal-judge-block-public-charge-rules-for-immigrants

I was planning on getting some kind of health coverage before the interview for my wife and sons but Now I'm wondering if it's ok to wait until they get here. If I do need to get something for them before the interview any suggestions?

https://www.visitorscoverage.com/