That sand looks fine. The lava rock at the bottom will be good to improve drainage. I bet the LFS is what rotted and caused everything to go haywire, but you are on the right path now and have good things to come. It is okay to put LFS as a top dressing as that will help protect the soil from overheating in hot sun.
Let me know if the okee giant does not come back next year as I may be able to help you out there.