If you listen to the rythm, it is a two beat count, just like a trot, but since the pairs are moving in lateral pairs, I think it IS a pace. There looks to be a bit of a moment of suspension, like a trot.
Definitely pacing. IMO this horse could gait nicely with a lot of work and consistency as when you go through and pause to see his break etc there is some potential -but if you're looking for an easily naturally gaited twh that won't be a lot of work to simply ride -definitely buy one that is walking when you buy it. This would be a big project.