I don't entirely know where to go with it, because knowing what we know that Forest and Katie know messes with my perception of things.
One way to view it is that Katie totally understood the problem Lyndon had with Forest, knew that he'd buy into the multiverse theory, and basically decided to murder him. But Katie already knew that was going to happen, so did she really "cause" that to happen? And as we see the outcomes of all these different worlds across different parts of the show, did this actually prove Lyndon's theory right and in another few multiverses he's alive and well and back at Devs (even though he fell in our current one)?
One way to view it is that Katie totally understood the problem Lyndon had with Forest, knew that he'd buy into the multiverse theory, and basically decided to murder him. But Katie already knew that was going to happen, so did she really "cause" that to happen? And as we see the outcomes of all these different worlds across different parts of the show, did this actually prove Lyndon's theory right and in another few multiverses he's alive and well and back at Devs (even though he fell in our current one)?


)