I made a hasty lookalike using tin foil in the same configuration, however the tin foil had wrinkles and therefore not so focussed but...
One flight on auto mode for frequency selection, in my back yard with mearby wifi including my own home, over trees etc....
I got a couple hundred feet LESS range with the reflector (3000’).
However I DID resume video downlink noticeably sooner on the autonomous RTH leg. One flight is meaningless, also I need to try the 5ghz band manually as well as more rural areas. First will get aluminum tape and make a smoother reflector.