There’s a suggestion on the Bikepackers thread that Spots aren’t brilliantly accurate.
there is that, but you can see where a tracker is just off track, and where the rider is obviously on a different road because the points are all equally spaced, and on a trail/road.
For example, SPray lake reservoir he’s followed the road on the east side, not the trail down the west, which looks like it would have involved turning off the trail from Banff to join the road, not just getting lost.
Then again south of Elkford, he goes down an entirely different valley (with a road/tail marked on google maps, rather than nothing, implying he took an easier route). Possibly lost, but you’d realise because there’s a 300m hill between them and a river just after the correct turn off.