Unmarshal JSON с использованием динамического ключа [дубликат]

Словарь сокращений, если вы решите пойти на поиск и заменить маршрут (я сделал).

Dictionary<string, string> _timeZones = new Dictionary<string, string>() {
            {"ACDT", "+1030"},
            {"ACST", "+0930"},
            {"ADT", "-0300"},
            {"AEDT", "+1100"},
            {"AEST", "+1000"},
            {"AHDT", "-0900"},
            {"AHST", "-1000"},
            {"AST", "-0400"},
            {"AT", "-0200"},
            {"AWDT", "+0900"},
            {"AWST", "+0800"},
            {"BAT", "+0300"},
            {"BDST", "+0200"},
            {"BET", "-1100"},
            {"BST", "-0300"},
            {"BT", "+0300"},
            {"BZT2", "-0300"},
            {"CADT", "+1030"},
            {"CAST", "+0930"},
            {"CAT", "-1000"},
            {"CCT", "+0800"},
            {"CDT", "-0500"},
            {"CED", "+0200"},
            {"CET", "+0100"},
            {"CEST", "+0200"},
            {"CST", "-0600"},
            {"EAST", "+1000"},
            {"EDT", "-0400"},
            {"EED", "+0300"},
            {"EET", "+0200"},
            {"EEST", "+0300"},
            {"EST", "-0500"},
            {"FST", "+0200"},
            {"FWT", "+0100"},
            {"GMT", "GMT"},
            {"GST", "+1000"},
            {"HDT", "-0900"},
            {"HST", "-1000"},
            {"IDLE", "+1200"},
            {"IDLW", "-1200"},
            {"IST", "+0530"},
            {"IT", "+0330"},
            {"JST", "+0900"},
            {"JT", "+0700"},
            {"MDT", "-0600"},
            {"MED", "+0200"},
            {"MET", "+0100"},
            {"MEST", "+0200"},
            {"MEWT", "+0100"},
            {"MST", "-0700"},
            {"MT", "+0800"},
            {"NDT", "-0230"},
            {"NFT", "-0330"},
            {"NT", "-1100"},
            {"NST", "+0630"},
            {"NZ", "+1100"},
            {"NZST", "+1200"},
            {"NZDT", "+1300"},
            {"NZT", "+1200"},
            {"PDT", "-0700"},
            {"PST", "-0800"},
            {"ROK", "+0900"},
            {"SAD", "+1000"},
            {"SAST", "+0900"},
            {"SAT", "+0900"},
            {"SDT", "+1000"},
            {"SST", "+0200"},
            {"SWT", "+0100"},
            {"USZ3", "+0400"},
            {"USZ4", "+0500"},
            {"USZ5", "+0600"},
            {"USZ6", "+0700"},
            {"UT", "-0000"},
            {"UTC", "-0000"},
            {"UZ10", "+1100"},
            {"WAT", "-0100"},
            {"WET", "-0000"},
            {"WST", "+0800"},
            {"YDT", "-0800"},
            {"YST", "-0900"},
            {"ZP4", "+0400"},
            {"ZP5", "+0500"},
            {"ZP6", "+0600"}
        };