Good place to meet up in the park?

My husband and I have a well-planned trip to Yellowstone during the first 9 days of September. I managed to plan our trip when the rates for lodging weren’t TOO ridiculously high so we’ll be staying inside the park our entire trip. (Yippee!) Upon hearing of our plans, my husband’s son, wife, and cousin decided they wanted to visit too. Because they’ve decided at such short notice, they couldn’t get lodging inside the park and are staying at a VRBO in Gardiner. The one day that looks like it would be the most convenient for us to meet up (though I’m sure we’ll find some other days) is on a day when we will be in the Old Faithful area (spending the night there and then heading back for a second night). With them being in Gardiner, what would you recommend as a good place for us to meet up to spend some time enjoying the park together? My husband and I are up for easy walks (I’m ~62 and he’s 69), but the “kids” will be interested in more scenic hiking. (I explained to them that we should try and plan something somewhat concrete being as communications in the park could be less than reliable. I’ve heard that texting isn’t much of a problem, but phone calls could be. So having a plan to meet up at a certain time/place would ensure we get to see them at least once. They live in different cities than we do, BTW. So we don’t want to miss an opportunity to spend time with them being as we don’t get to see them often.) Maybe someplace like the Museum of the National Park Ranger or the Norris Geyser Basin Museum and Info Center? Or further north such as Sheepeater Cliff Picnic Area? Or should we head closer to them and visit the Albright Visitor Center as a group? (This will be our first trip to Yellowstone, so I’ve tried to become familiar with the area but not knowing altitudes of certain areas, etc., may make me naive about what to consider.) I GREATLY appreciate your suggestions and recommendations!