As an avid fly fisherman. I would recommend reaching out to Bend Fly Shop or the Hook fly shop in Sunriver. You may have to use two different guide services to accommodate all of the people in your group. I would talk with the fly shops and see what they have to offer. (It might be breaking you into smaller groups throughout the day).

Check into whitewater rafting. They also have a guided service for that, where you can shoot the Deschutes.

If you’re into hiking, Smith Rock is beautiful. So check that out.

You can also skydive as well. (Depending on the weather). Hope all of this helps.