What is in the envelope Tyler received after from Jason after he died? Why did Jason leave him the envelope?

Tyler opens an envelope addressed to him by Jason. The envelope contains multiple credit cards and counterfeit identifications, as well as a letter from Jason. In the letter, which reads like a testament, Jason explains that he is sorry for using him as an accessory to his own quest for the truth. He says that he will likely be the target of governmental inquiries and that he should go in hiding. He adds that there are too many secrets hidden in the Martian archives for the politicians to allow them to go public. The accompanying documents, falsified but reliable, should help him go in hiding relatively safely.