I’m studying how zero knowledge for quadratic arithmetic programs works (GRO16 page 17) and try do understand proof simulation part.

If I understood right, if malicious party knows 𝛼,𝛽,𝛿α,β,δ from setup it will be possible to construct 𝐴,𝐵,𝐶A,B,C that will satisfy verification equation.

Are there are any other combinations of setup parameters that can help to simulate a valid proof?

Also, I would be grateful for a useful link / or research work where proof simulation for QAP this can be described.