Why don't you call a couple of the tour companies?

I googled and found one company that offers a tour that includes a whitewater raft trip and helicopter up to a viewpoint of the west rim (but not the skywalk). Another company offered a smooth-water boat trip and the skywalk.

Neither of those are exactly what you want. It may be a matter of geography and logistics. Call a tour company or two or three and find out what they have vs what you want and ask them to refer you to a company that might have what you want.

thank you, we do have a tie difference problem as we are in Australia.
I think we have "googled" everything there is. Maybe there is a design your own tour with someone.

thanks again

Have you tried emailing the tour companies?

You must have seen what I mentioned: smooth water with skywalk or whitewater with a West Rim viewpoint (may have been Guano Point and another).

One of the google results linked to a tripadvisor review of such tours. There were some negative comments about the sky walk. There is the price, around $30, to get onto the skywalk. Also, you can't take a camera or phone onto the platform and if you want a photo there you pay $30 to the tribe's photgrapher. A couple of the reviewers thought that Guano Point was spectacular. One reviewer thought that calling the raft trip a whitewater tour was a stretch (i.e. it was pretty smooth).

You might be better off renting a car and driving. You might save time and money. Spend a night there (where, I don't know).

I mentoned geography and logstics. You may have noticed that the helicopter tours from LV don't go to the Sout Rim. It is because the SR is out of the chopper range, so you have to take an airplane to GCY airport. The tour that has skywalk + boat requires taking a bus from LV to the Boulder City airport to get the helicopter. Maybe they use that airport due chopper range, or maybe somethng else like the cost of the helipad use.