Even if he did have the authority/power to order her, what does that actually mean in practice?
Guards dragging her kicking and screaming, her injuring guards or making allegations they have assaulted her so there has to be an investigation and the guard suspended during that?
What about if she sits in the court shouting out, crying out, disrupting proceedings, is that productive and effective? Making it all about her?
Now she might not do those things but a lot of prisoners do/would, I couldnt care less if convicts are present in the court or not, in fact I find it a more powerful message to people that justice is served whether you choose to engage with proceedings or not.
I dont know why people are so hung up on this, its irrelevant if she attends, it means nothing. The sentence is the sentence, she has already been convicted, the job is done regardless of whether she is sitting there to hear it or not.