I think you passed the gps test part, lightly. I mean it has dual band gps which by itself is a great feature to achieve (if done correctly) batter accuracy on all situations.
Also, in the review you write (and i quote):
QuoteThe Mi 9T Pro deviated slightly from the route that the Garmin recorded as the photos below demonstrate, but not worryingly so. Overall, the device is accurate enough for general use as a substitute sat-nav or bike computer.
But, looking at the pictures you have to prove your point i see that the Redmi has achieved much better accuracy (look at the road line, the bridge 2 sided way). So it's accuracy is much better in fact than the Garmin (and not the other way around).