Wow. Glad nobody died. A swiftwater rescue course is worth its weight in gold!
I know it's tempting to do anything to save somebody, but there can be serious consequences to tying a rope to a lifejacket. (the class IV rescue jkts have releasable belts that rescuers are connected to) Good effort in the rescue!!!

If you had not been there it could have been real bad...

...And ya caught fish!!