You don't have any rights because you are not the defendant. However, I see two options here. Camp out at the attorney's office until you get him in person. Or send him a certified letter stating that you will file a complaint with the state bar if he does not speak to the defendant (not you) within a certain number of days. He doesn't have to talk to you about the case, but anyone can file a complaint with the Bar
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A judge is usually reluctant to change appointed counsel. I agree that you should send written correspondence to the attorney and make him/ her aware that you are considering contacting the State Bar.
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