I think that tracing Harry Maybury's family is our best bet to finding living Maybury relatives. He was the youngest Maybury sibling and he had two sons. Unfortunately, the 1911 British Census hasn't been released for all areas.
At the time of his marriage, he was a tool maker. The witnesses for the wedding were likely his wife's (Emily Glew) siblings. Lizzie was already in the US. I am still trying to find her older sister, Carrie.