I wanted to chime in here and say that I have same problem with iCue.
Contacted Riot, they gave me a few options on how to fix it and none worked. I will be contacting them with logs and asking if they can whitelist it. Otherwise we will have to wait for Corsair to fix it.
Also, related but unrelated... In same week when Vanguard, iCue and FACEIT AC were updated, that is when the problem started.
Vanguard does not like iCue's CPUz currently and FACEIT AC does not like Afterburner (newest version) for some unknown reason. FACEIT AC wouldn't even lunch, after few reboots, safe mode uninstalls and some tinkering, I got FACEIT AC to work, but Vanguard is impossible if you want your iCUE to work properly. My CPU was even cooking once (as I forgot to edit fan curves since they were based on CPU temp). Now I put my fan curves to be based on AIO temps, and AIO is on extreme (just in case).