Sponsor documents for visitor visa

I'm in the UK on a dependent visa for the past 4 years and my parents are applying for their first UK visitor visa, I'm going to sponsor their application but there are discrepancies in my parent's name due to the wrong name in my birth certificate written by my maternal grandfather:

• father's name on my passport & birth certificate is: xxxxx
  • mother's name on my passport & birth certificate is: xxxxx
    
    
    and their own passport and all their documents have:
    
    • Father's name: xxxxxxx
      • Mother's name: xxxxxx
        
        
        When I filled UK family visa application & FLR-M I followed what was written on my own passport.
        
        My grandfather wrote xxxx and xxxxx in their names as it's customary in our religion to add that name, my father is going to create an affidavit explaining the situation that both names belong to the same person. Has anyone experienced anything similar, this is stressing me out? Should we be hiring a lawyer? please help.

Hello, I want to sponsor a visitor visa for my mother from India, I bought a house in April in the UK but due to the current backlog with the Land Registry, I have not received the title deed yet, and I contacted the bank for a mortgage statement but they said they give an annual statement for a mortgage but can give me redemption statement, will this work as proof of ownership for my mother application? what other documents do I upload from my side? please help, this is my first application for my mom.