Paul, I can't view the video, it says it's private!
About the drain hose, I didn't think it was standing too low!
I thought it might have been too high (compared to when you tested the machine in the garage) or binding! Or the drain port might have been clogged.
These machines should drain by gravity when the drain hose is left on the ground, if it drains quickly by gravity, you can tell the drain isn't clogged. If it doesn't pump the water while running if you lift the hose, there's probably an issue with the impeller but we had a look at yours and it seemed fine (but unlike the newer ones, it's not made of rubber so it might break suddenly). But since it drained fine afterwards, I suspect that the hose might have been kinked or compressed against something.
That happened to me once with my 1957 Unimatic (the washer was too close to the wall and the drain hose was squeezed between the machine and the drain pipe which is external to the wall in my installation). The washer didn't spin the water out as it tripped the motor protector when it attempted to spin with a full outer tub! And this machine still has a thick drain hose just like the one you used on your 1959, not one of those thin replacements...
The same happened with my 1972 Inglis Royal 100 as the drain port had made a complete turn while manipulating the machine to fit in place (it was a tight fit!) and the internal part of the hose was kinked.