First, you can't ask that question about Zoro since they were not paying attention to him in his scene. There is no speed feat here.
Second, yes and no for Hakuba. Not all people were paying attention to him, so only the ones around him were blitzed, not the rest. He was too fast for those who were paying attention, so yes to your question, he was too fast for them seeing him.
But, actually, that doesnt matter since Bartolomeo couldnt see him and Bartolomeo > everyone in that block except Hakuba. So even if they were paying attention, it won't change the outcome, they would get blitzed.