@Kakapo Well, I just do not think it is a Rhinobeetle. In usual, Rinobeetle (犀金龟or兜虫in Chinese) means Dynastidae, and Cetoniidae is called Flower beetle (花金龟). Interestingly, for genus Theodosia, Mycteristes and Phaedemus, we call them 兜花 (Rhino-flower).
"Rhinobeetle" is just a common name (and an invented one, as Dynastidae are used usually to be called "Rhinoceros beetles"), and hence do not have rules and you can call anything as "rhino beetle", especially the beetles with horns in their heads independiently of if they're Cetoniidae, Dynastidae, Scarabaeidae...