Vite SSR React SEO not rendering on Vercel server but on local machine

So I have been struggling to get setting up my vite SSR react server right so it can render my react-helmet-async meta tags.
Worked my way on getting it to render the meta tags and links with this entry-server.jsx snippet:

import React from "react";
import ReactDOMServer from "react-dom/server";
import App from "./components/App";
import { StaticRouter } from "react-router-dom/server";
import { Router, helmetContext } from "./routes/Routes";
import { Helmet } from "react-helmet-async";

export function render({ path }) {
  const html = ReactDOMServer.renderToString(
    <StaticRouter location={path}>
      <Router />
    </StaticRouter>
  );

  const { helmet } = helmetContext;
  const head = `
  ${helmet.title.toString()} 
  ${helmet.priority.toString()} 
  ${helmet.meta.toString()} 
  ${helmet.link.toString()} 
  ${helmet.script.toString()}
  `;
  return { html, head };
}

Which worked out with this snippet on the server.js:

    let template;
    let render;
    if (!isProduction) {
      // Always read fresh template in development
      template = await fs.readFile("./index.html", "utf-8");
      template = await vite.transformIndexHtml(url, template);
      render = (await vite.ssrLoadModule("/src/entry-server.jsx")).render;
    } else {
      template = templateHtml;
      render = (await import("./dist/server/entry-server.js")).render;
    }

    const rendered = await render(url, ssrManifest);

    const html = template
      .replace(`<!--app-head-->`, rendered.head ?? "")
      .replace(`<!--app-html-->`, rendered.html ?? "");

It works on my local machine, don’t get me wrong. It renders the server side when I build and preview; I know this by viewings the source code on my Google Chrome browser – not via inspect or dev mode.

But now, when I deploy my app to Vercel for some reason the SEO doesn’t get recognised by crawlers and when I view the source code, the meta tags and html doesn’t get injected, therefore it only gets rendered on the client side.

I have a feeling that this might be an error on the Vercel server but I can’t be sure about that.

I want to understand how I could go about it.

Here is the project repo:
https://github.com/unnamed-lab/fullmoon-real-estate