At any age, I don't think a human can run 25 MPH or more to out run a rhino. Hide from one is possible (?), as they don't see all that well

Some people forget these are wild animals. They can be unpredictable. Getting out of the vehicle to "get a closer picture" is often a bad idea. Guides know better, but they live and die on tips...so maybe they may let an insistent passenger take too many chances?