Problem with wordpress links on a live site

The welcome page “exists” since I can access it when I search for it, though trying to go to its link directly give me a 404 as well. As an experiment, try changing that page’s slug to welcome2; if it works now, check if you have any custom rewrite rules set up that are overriding the welcome page.

I see that there is a welcome.html file present there which is a filler if your site is not yet up.

Rename it to _welcome.html, set your page’s slug back to welcome and try accessing your welcome page directly again afterwards (force re-load the page since you might still see the 404 come up at least once).