CMBG: Admit your mistakes
There is a simple rule that mariners and engineers use. If something can go wrong, then something will go wrong. Known as Murphy’s Law.
I see that law applying to the misguided plans of the Botanical Gardens. May I suggest they admit to their mistake. Restore the land so damaged back as a Memorial Forest. Offer trees to anyone, or group that will plant a tree in memory or celebration of a life. In doing so win the hearts and minds of all affected by their terribly shortsighted plans. The cost here is not a factor. To do nothing now will increase the cost well beyond our imagination.