from my personal experience replacing old deck boards on boats mostly '60's Chris-Craft the decks were Teak, hard as hell, and let me tell ya the grain in ONE piece repeats itself A LOT so that "pattern" so to speak would be a Teak trait, HOWEVER it looks to have been sealed with some type of protective coating most commonly it be a Shellac, I'd almost bet money I don't have, The REAL question is, you got it for a good price I'd say Teak is NOT cheap by any sort of the imagination, BUT because of this I'd love to know what blade they used to cut it and do the routering/shaping to it, as that wood is like routering steel I-Beams!
The darkness of the wood seen in the video I bet would be the natural darkening over time "age" of the coating, which the old stuff, was VERY WELL KNOWN in the wood working field to be a trait as well, to re do ANY of it, you'd have to merely "soften" the coating with a remover, BUT NOT to remove it, but pull the darker areas to spread that excess over the lighter area to get a uniform color over-all....
Be sure to keep NEW drill bits in hand at all times working on the wood, and saw blades made for steel cutting WITH teeth, my suggestion would be Frued, "Diablo" blades called "Steel Demons" BEST blade you can find for such I got one and cut stainless steel counter tops with a single blade that STILL cuts wood without ANY splintering.....This blade? I've had going on 2 and a half years, paid $40 at Home Depot, and you just can't beat it........ I don't even change the blade to go from steel to wood anymore....And it rips through nails without loosing a single carbide tooth!
HTH