Just wanted to update everyone! Google Search Console has finally found some URLS, hurrah! It took over a month since the last submitted date for Google to start finding them. I guess patience is the key.
Thank you for all the advice. It has been truly appreciated.
For those having the same problem, I'd suggest going through the advice KieranR gave too, to ensure there aren't any other issues, otherwise I think it is just a waiting game unfortunately.
Good luck everyone!