This is a bit of a general question :) but

 From:  Michael Gibson
5009.9 In reply to 5009.8 
Hi Steve, it may take me a while to get to the bottom of why your original fleur had that damaged area in it.

In the meantime, try the attached updated version.

For this version I mirrored over the fleur from the other side and trimmed it into place, also deleting a couple of those little tiny micro shelf areas as well, and this version looks like it should now boolean union ok.

- Michael