Salaah

Woman performing salaah while wearing a niqaab

Q: I would like to enquire about a woman's salah when she is wearing a niqab/burqa. 

1. Is a woman's salah valid if she performs it while wearing a niqab/pardah, covering her face, in the presence of non-mahram men? 

2. I have heard that during sajdah, the forehead must make direct contact with the ground and that there should not be anything obstructing it. Does wearing a niqab or pardah interfere with the validity of her sajdah? 

3. If she performs her salah with her pardah covering her face because non-mahram men are present, is she required to repeat that salah once the non-mahram men are no longer present? 

4. What is the ruling regarding burqas that get in the way during sajdah? Sometimes the loose material of the burqa falls forward and gets underneath the forehead when going into sajdah. Does this affect the validity of the sajdah? 

5. Similarly, if a woman wears a burqa that is low and hangs over her forehead, covering it, must she adjust it before performing sajdah to ensure that her forehead makes contact with the ground?

Reading the two rakaat nafl after witr

Q: My question is regarding the 2 rakaats after the witr salaah, what is the law regarding it? 

I have read in you fawta https://muftionline.co.za/node/33039 that our elders would read this salaah. However in ahsan ul fatwa, Hadrat Mufti saab explains this is not mustahab and also that no fiqh kitaab mentioned this. He also gave an answer for the hadith which shows these two rakaats after witr. 

What is the correct view in regards to these two rakaats?