What if most of the volume are trades in normal price (~$1), and ONE small trade is the spike? (=$1.03)
Since the "high" part of the candle is NOT THE AVERAGE price but the HIGHEST one, it will still show there.
...or not?
E.g. Buying 10 TUSD for $15
It will still show as a spike in the candle chart, regardless of volume.
Am I correct?
Nope. If you look at the order book, an order like that wouldn't move the price even $0.0001.
On that one hourly candle that spiked to $1.0333 in the OP's screenshot, there was $1.73 million traded. That's what caused the spike. Somebody holding a lot of DAI wanted out of the market fast.