Ok so I came across this youtube video and i saw the comments saying he was infact boosting his duo so i decided to investigate this myself. I took a look at Derkes tracker and I saw that she averaged a whopping 0.57KD in the 33 games they haev together despite having a 72% winrate together. Upon further investigation I also found that she dropped down to diamon from immortal 1 inmonth after Derke stopped playing with her... Coincidence? I think NOT!
Proof of the boosting theres multiple images in this so scroll https://imgur.com/a/z9ZkPMJ