I would try the local bike clubs and find member who are interested in multi-day rides.
There are also charity organizations who provide logistics and support for multi-day rides and all you need are sponsors. One advantage of riding in a group is that being more visible to motorists there is less chance of getting clipped by someone busy monitoring their cell phone messages and ignoring the road. And there are the U.S. tours like the Great Ohio Bicycle Adventure in June for example. Other states have their own tours as a way to boost tourism.
I will also mention that on my last 3 travels with a group there was one person who came despite having a cold infection and they spread it to everyone in the group.
Having started touring in 1968 and making my first trip the length of the California coast in 1971 and creating the first bike map for the route that was published by the CA Division of Highways, Once I could afford to do so I quickly switched to staying at motels and eating in cafes as much as possible. I could travel lighter without camping equipment and a cook stove and fuel and staples and it is a treat to have a comfy bed and a hot shower available at the end of the day.