The first video ... the lack of one arm should give you a hint to run away. The second video, that contraption looked like a Redneck guillotine.
Reminds me of a friend who built a log splitter using a one axle utility trailer. The ram was 6 inch in diameter, with a 2 foot stoke, so it could bend the Empire State Building.
For power, he bolted a air cooled 60 HP VW engine to the trailer. Anyone need to split a Redwood or Sequoia tree?
Northern tool has about 30 different log splitters, and some of them were on Sale when I checked last week.