Sterling was looking for the penalty - but yeah, it was totally a foul.
But, not calling the foul (for whatever reason) and carding Sterling (again mystifying), and on that basis concluding that the ref is corrupt - is some sort of tin-hat conspiracy lunacy IMO.
The ref fucked up - big time.
But was he an intentional cheat? I don't think so.
For that matter, was he totally incompetent - I also don't think so. He largely called the game fairly outside of these moments.
Again - if he was corrupt/incompetent - he could easily have blown for a penalty on Messi in our box (wrong call but if totally biased he would have) and he could have blown for hand ball against Kun.