I note that you post is nearly 10 years old, but I am replying anyway, in the hope your e-mail address has remained unchanged. Did you ever receive a satisfactory reply to your question, I wonder?
I definitely know the family link between Hugh Woolner and Percival Waugh, as well as something of Percy Waugh's descendants. I am not aware of any link with an opera singer (??) but I do have some details for Percy Waugh's Hungarian wife.
I don't know whether you are still interested, however I would certainly like to know something of the supposed opera singer link, and whatever else brought these two men (first cousins) together in Budapest.