It's not in anybody's best interest for a daughter of the seemingly powerful and well-connected Alarcon family to be fingered as the Gold Knife Killer, including by the governor who insists Ayala stop investigating--especially if she really is not the killer. It does not make sense that Dona Teresa is able to pull strings often, but none this time. Plus, given that Alfredo previously was convicted of murdering a woman, Cristina, suspicion should have fallen on him in this maid's murder. The simple fact Sophia was found with the body is not great evidence--after all, someone has to find every murder victim, and a murderer won't be so careless as to scream like Sophia did.
It's odd that no one in the family helps Alfredo search his papers for evidence Sophia was away during some of the Gold Knife murders. He works at it obsessively, yet never asks Alicia or Javier--who are quite at their leisure--for help, and they also don't have the same idea he did, and offer to help. One of them might even have a letter sent from Sophia from abroad, or some other evidence Alfredo didn't.
In the previous season it was not really explained how Gonzalo's father ended up in prison, but there was some sort of con involving a mine that turned out to have no value. As Alicia and Julio discovered, Diego held proof that Carlos Alercon, and not his brother (Gonzalo's father) actually owned the mine, and thus Carlos and not the brother was the guilty party. This same mine seems to be at issue in the present episode, as Gonzalo wishes to destroy the property deed. Yet he also calls it his father's mine, as if Carlos only had partial ownership. This is at odds with the previous season's assertions that Carlos was the owner, and Gonzalo's father had no claim and was thus innocent in any con. Yet now Gonzalo seems to think he can prove his sole ownership of the mine once the other deed is destroyed.
Further, even if the Alercons discovered the mine's new value, there is still the matter of the ownership deed proving Carlos' crime, which might give the government grounds to seize the mine as it was involved in the crime. Given that both parties don't want the deed to come to light, Gonzalo should at least consider offering to cut his family in on the deal a small amount to keep them happy, as he can be sure they would think twice about pressing their claim on the mine if it meant Carlos' crime going public.
Further, even if the Alercons discovered the mine's new value, there is still the matter of the ownership deed proving Carlos' crime, which might give the government grounds to seize the mine as it was involved in the crime. Given that both parties don't want the deed to come to light, Gonzalo should at least consider offering to cut his family in on the deal a small amount to keep them happy, as he can be sure they would think twice about pressing their claim on the mine if it meant Carlos' crime going public.