Hi, Art. By the way, you are invited to the meeting also. See below. We'll get back to you on whether it's at the Home Depot in Hawaii or John2000's place in Holland. LOL
Concrete manufacturters do have products that they say will bond and are available in DIY quantities. I'm sure that Sacrete makes one and there may be others. As a matter of fact, I believe that they make 2 varieties, depending on section thickness. If you decide to go this way, I suggest building a frame out of wood to fit the area you want to fill and of the correct thichness. Then scree to the wood to get the slope. After it has set up for a while, come back and finish trowel.
Good luck and let us know how it turns out. Henry in MI