I'm using a rockit cool direct die kit with the ek evo supremacy block on a evga z390 dark. I used the included water block stand offs, I just removed the white plastic washers that go between the stand offs and motherboard. Rockit cooling has a youtube video on how to install the direct die with the Ek evo.
Have you tried a lower voltage ? Your Vid is so much lower than what voltage your running. My 9900KS has a VID of about 1.24vs @ 5ghz during a cinebench r15 run, however my chip is 5ghz, 8hr Real bench stable with a bios voltage setting of 1.2vs using +25% vdroop setting. Ive tested 3 9900k's, 2 9900KS's, and they all could do 5ghz at or below the listed vid.