How to perform Eval on an async function (like a fetch operation)

[cardilloscreations]

In my use case, I cannot use the built in hijacking because the web page hooks the fetch function and it will be easier to just do a fetch and get the JSON I need from their related API (needs a session to be established first). So I need to perform an Eval with an async fetch operation. When I run a command in the console (even a non-headless browser launched by go-rod in the same way - for testing purposes) it works fine. But when I try various combinations of Eval with AwaitPromise true, it does not work. It's like the async wait just times out.

I've tried this for example:

func FetchJSONData(p *rod.Page, URL string, to time.Duration) (rt *proto.RuntimeRemoteObject, err error) {
	return p.Timeout(to).Eval(`async () => {
		const response = await fetch('` + URL + `');
		if (!response.ok) {
			throw new Error('fetch error! status:' + response.status);
		}
		const data = await response.json();
		return data;
	}`)
}

If I strip that down without the function in console it works fine. Also, if I run it as an IIFE, it works fine in console and the promise returns with the response, for example:

(async () => {
		const response = await fetch('https://some-url-in-cors-domain`');
		if (!response.ok) {
			throw new Error('fetch error! status:' + response.status);
		}
		const data = await response.json();
		return data;
	})();

Tracing through go-rod a little, I see this is done with an apply statement so I'm wondering if that's the source of the problem? Any idea what I'm missing here?