Check that channel ID is part of game.

gistfile1.txt

var game = {
    otherKeys: "values",
    channel: 187382131313,
    channels: {
        controlChannel: 311313123123,
        otherChannel: 13131313123,
        channelList1: [
            12112321313,
            12312312311
        ],
        channelList2: [
            2183213213,
            132213231132
        ]
    }
}

var channelIds = Object.values(game.channels) // Array of both channel IDs and more arrays.
/*
    [
        311313123123,
        13131313123,
        [
            12112321313,
            12312312311
        ],
        [
            2183213213,
            132213231132
        ]
    ]
*/

var flattened = channelIds.flat() // Array of channel IDs
/*
    [
        311313123123,
        13131313123,
        12112321313,
        12312312311,
        2183213213,
        132213231132
    ]
*/

var isChannel = channelIdToCheck in flattened; // True or false value.

// Inline version:
channelId in Object.values(game.channels).flat()