Some Saturday AM suggestions that will be low impact:
-Visit some of the scenic spots right in Decorah. Dunning's Springs, the fish hatchery, Twin Springs, and Palisades Park are all pretty cool and don't require much of a physical investment. Dunning's Springs in particular is quite beautiful and extremely accessible. Go earlier because it gets overrun closer to noon. I'm an avid mountain biker and use the Dunnings parking lot to start most of my rides. I usually start before 7AM on Saturdays because it turns into a zoo.
-Downtown has some nice shops. Shopping isn't really my thing, but some folks like it. Impact Coffee is my favorite place for a cup of joe, and the owners are awesome people.
-Malanaphy Springs is a longer hike (2 miles round trip) but it's fairly level. Absolutely beautiful and worth it, but maybe too much for your crew.
-A little road trip to fill the morning could be really pretty. I'd recommend doing something like grabbing a cup of coffee at Impact, and then taking the Pole Line Road to Cresco. Very scenic drive that goes along the Upper Iowa at a couple points, as well as some tributary streams. Stop at Dough & Joe in Cresco for the best donuts in the Driftless Area. From there, head back east and drive through Bluffton. You can see the bluffs from the bridge in town. From Bluffton I'd head towards the Locust School. From there, veer onto the Sattre Ridge road and go through the old town of Sattre. It was found to be the most remote place in Iowa per a DSM Register study in the early 00's. From Sattre, I'd work through the Upper Iowa Valley and stop at Heritage Valley. It's a beautiful viewpoint of the valley. From there, wind your way back into Waukon and stop at WW Homestead Creamery for the best damn cheese curds in Iowa (and as good as anything in Wisconsin). At that point, you're only 20 minutes from TG and you can either cruise 9, or take the much more scenic Old Stage Road back to Decorah.
-A short morning float on the river could be fun too, but again, water levels are lower, and I don't know how adverse to walking your group is. If you did that, I'd recommend the shortest float into Bluffton (start at Chimney Rock bridge). It will take you past the quintessential bluffs.