I don’t know what happened. Dope means they toyed with her and that is why she broke.
I hate the word surreal. We all have some commitment to Bayesian analysis. Recognize that it is a probability and all probabilities include frustration as an outcome. Calvinism, the widely held belief enshrining Bayesian outcomes that things are as they are, frequently fails. This may be explained as fractal dynamic or failures of framing, but may simply be the consequence of chance. Confusing improbable with surreal simply means that your smug world view has been challenged by experience. Likely is not always so.
Explication still requires likely. We are indisposed to accept the miraculous, even when it is so. In the case of Sandra Bland the difficult anomaly is that she died stoned. If you believe that she somehow smuggled the dope in herself, I suggest you attempt it. If all the various formality and process of incarceration guarantee anything, they ensure that you will not have marijuana in prison. The explanation requires that Ms. Bland, in anticipation of her incarceration, secreted marijuana on her presence in some way unnoticed by her guards who deal with exactly that scenario every single day of their careers. If Waller County cannot explain the marijuana, they have no legitimacy.
Some believe that Sandra Bland was murdered. This is an excellent example of the difficulty of framing. It is likely that you have been inside. If you have, then you are well aware that prison is a very serious time out. We like to think we have internal resources. But as you read this you can select an entertainment source, order a pizza, or step out for some air. You can’t do those things in jail. Most of us are not good company and would resent being the sole source of someone’s divertissement, even or especially our own. It is likely that Sandra Bland obtained the marijuana from the guards. It is unreasonable that they would give her dope and then murder her. I hope that Sandra Bland was murdered. I think it was far worse.
Sandra Bland is depicted as fragile. I see her as self-reliant and adaptable. I doubt most of us would have lasted as long. Why would the guards give her dope? What could she do for them? As you have come this far, I will be explicit. Harassment of prisoners, particularly women prisoners is common. One may say likely.