Tier 4 - Dependent Visa - Appointment Issue

I applied Tier-4 dependent visa for my wife. I have paid visa fees and Health Insurance payment. However, whenever my application re-directed to VFSGLOBAL site to book an appointment, it gives error that due to COVID-19, appointment is not available at your application centre.

I want to submit my bio-metric in Islamabad Application Centre.

Application Detail:
Application centre for bio-metric: Islamabad, Pakistan
Visa Type: Tier-4 dependent

I have some queries,

1. Is this problem for everyone or it's technical issue from their website? What could be alternative to book an appointment? I have been told by someone that website is having update on weekend, that's why booking is not possible. Website will be back to normal on Monday.

2. Whenever, application is directed to VFS website, they are also asking me upload scan documents (TB Test, Uni letter, Bank statement, Proof of relationship). Do I need to upload scan documents? or it will be done at Gerry Office?

3. I'm recently married, what sort of evidence I can provide as a proof of relationship. I have Marraige Certificate, FRC, Nikkah Nama (Urdr) and Nikkah Nama (English Translated). Do I need to submit whatsapp chat or wedding pic as well?

Thank you