Unfortunately, you might have to be physically at WDW - I'm not sure. What I do is open the
MDE app and click on the magnifying glass to Search for the restaurant I'm interested in. I just now put in Geyser Point, and it pulled up the site for me with hours, menu, etc. There was also a Join Walkup Wait List button, but when I clicked that it said I was too far away (I'm at home!).