Just saw a few connections attempt declined by SteamChecks. Nothing was sent to the Discord Hook. My Config:

{
  "AdditionalKickMessage": "xxxxx",
  "ApiKey": "xxx",
  "BroadcastKick": false,
  "CacheDeniedPlayers": false,
  "CachePassedPlayers": true,
  "DiscordRolesToMention": [],
  "discordWebHookUrl": "https://discordapp.com/api/webhooks/xxxxxx",
  "Kicking": {
    "CommunityBan": true,
    "TradeBan": false,
    "PrivateProfile": false,
    "LimitedAccount": true,
    "NoProfile": true,
    "FamilyShare": false,
    "ForceHoursPlayedKick": false
  },
  "LogInsteadofKick": false,
  "Thresholds": {
    "MaxVACBans": 3,
    "MinDaysSinceLastBan": 14,
    "MaxGameBans": 2,
    "MinSteamLevel": -1,
    "MaxAccountCreationTime": -1,
    "MinGameCount": -1,
    "MinRustHoursPlayed": -1,
    "MaxRustHoursPlayed": -1,
    "MinOtherGamesPlayed": -1,
    "MinAllGamesHoursPlayed": -1
  }
}​

make sure the webhook is correct.. You can test it with the command steamcheck steamId and put in an offending steamId.. 

Of course its correct ;)

Did you test an account with the command?

Yea like sayd. Im getting douzens of kick messages from SteamChecks in Console. But nothing is sent to Discord as sayd. No Exeption.

Is there the Role need to be set in config?