My question is about cheese contains beef rennet is halal if animal is not slaughtered according to Islamic law . And I also found this if you can help me out this website is from South Africa
I agree with the answer that is provided through the link in your question.
If the rennet is derived from the Halal animal regardless of it being slaughtered according to Shari'ah or not, would be Halal. If one would like to avoid such product then that is their choice.
And Allah knows best.
Mufti Ikram ul Haq
Fatwa Center of America