That video reminds me of the “Snurfer” (Sherman Poppen, 1965). It was the pre-cursor to the modern snowboard. Burton, a carpenter, modified the Snurfer concept. With his new creation, the snowboard was born.
Mountainboards were developed as off-season snowboard trainers. Several people did DIY builds. Those usually involve 1/16” maple veneers and “presses” (screw-down, hydraulic and vac-bag). While the process is a bit different for snowboards, the concept is similar.
Regarding rocker, pretty sure snowboards use “camber” (like mountainboards) for “pop.”