If even there weren't a precedent for it, that in itself does not prove anything.
And as to Roglic's glowing bike, I still think that hub motors are unlikely to be used for reasons that were extensively discussed earlier. I would be very interested what other reasons there could be for this supposed anomaly. Also if it is correct that it was not even the team's own rear wheel, and this seems to be the case judging from the images, this makes it even more unlikely to be a hub motor. What are the chances that the neutral car would be distributing hub motors at random to riders stricken with a flat tyre. Also how would they know the exact make up of the motor that Roglic or LottoJumbo requires? Not all batteries are compatible with every motor etc. Also it would involve even more people who are in the loop and in on the conspiracy, because it would require the neutral car to be in the know that they use hub motors and which types (which make en even stronger case for the use of crank motors in the downtube, because that would not require such an elaborate set-up).
The hub by the way is glowing less brightly than Roglic's bum, which we can assume to be around 37 degrees Celsius, so we cannot actually call the hub piping hot.