I don't think you're betraying Samael Aun Weor by reading other authors. Samael himself read the work of dozens (possibly hundreds) of spiritual and religious authors.
What is important is to practice and work.
Regarding Krishnamurti, he was a great master, and Samael Aun Weor points this out himself. However, due to some trauma in his childhood he was unable to teach to his full potential. But his teachings are still excellent.
It's also worth mentioning that Krishnamurti can be very subtle. There are times when it appears like he is saying something contradictory to Samael, or some well-established Scripture. But when you really examine his words carefully you see he is actually in complete concordance with them. Like the work of any great master, his words were not meant to be read like a newspaper. You have to reflect carefully on what he says.
Also it's important to remember that these teachings are not the exclusive domain of Samael Aun Weor. The knowledge we share here is universal, which is why we draw from so many different scriptures and traditions in the material on this website. We encourage people to study the work of many great masters, and there's no reason to feel like you are committing a betrayal when you do so.