discord-player-play-dl/docs/youtube/proxy.md

Using Proxy to avoid 429

const { Player } = require("discord-player");
const HttpsProxyAgent = require("https-proxy-agent");

// Remove "user:pass@" if you don't need to authenticate to your proxy.
const proxy = "http://user:pass@111.111.111.111:8080";
const agent = HttpsProxyAgent(proxy);

const player = new Player(client, {
    ytdlOptions: {
        requestOptions: { agent }
    }
});

You may also create a simple proxy server and forward requests through it. See https://github.com/http-party/node-http-proxy for more info.