More clarifications too late to edit.
For the setting triangles, I would cut blocks that were 13.5" and slice along the diagonal. That will leave the outer edge as bias but you will soon be stabilizing it with the border sashing. You can also cut the setting triangles so the long edge is straight of grain, but I'd do it my way
If I entered it in a show with similar fabrics, I would list it as "
Inspired by Botanical Oasis designed by Anne Rowan".
I had some fabrics pulled out as a potential project, I think this idea will work for them but it will be a very different looking quilt. I have the fabric in the wash as we speak... My inner unit will be based on a 2x4" flying geese unit so instead of drawn out with a 12" center I will have an 8" center, my color choices and placement will be much more graphic, and I will probably be using squares and a diagonal set instead of the triangle technique. Additionally, I would make the top as a rectangle and not a square as designed. It will be for donation, but if I showed it, I would say "
Based on Botanical Oasis designed by Anne Rowan" and maybe even break it down slightly further as "Block Based On..."