NOTAM Trees
Firstly, I am truly sorry that you have lost two colleagues in this incident. A tragic loss.
Secondly, I'd like to say that I'm no pilot but a long time visitor to your forum. Therefore please forgive me for wading in to your professional arena.
The reason to felt to respond to this thread is that the thread inadvertently strayed in to my profession; that being Trees.
I am perplexed to read that the Airport Authority in this incident had undertaken tree height reduction works at the property belonging to Mrs Benson (top of the ridge).
We refer to trees in my industry as Self Optimising Mechanical Structures. The key bit in that is the Self Optimising. That is what trees do. You knock 15 feet out the top of a tree, the tree will Self Optimise and react through re-growth (there are very few exceptions). Depending on the species, the tree can be back up to that height within just a few years. on occasion a lot less.
So why undertake this type of works on trees that are clearly a long term issue and are listed and catalogued for NOTAM purposes. For me, if that 15 feet is going to make an approach 'safe', there is something wrong. It's only another 15 or so feet to the roof ridge of the house!
Again in our industry we use the phrase Right Tree In the Right Place. Therefore, if these trees are such a deal breaker for an approach on to this runway, don't prune the top out. Prune an inch off the bottom and re-plant three new ones out of the approach path.
Even if these works were justified to allow a increased visual on the PAPI/runway lights, it's still not a solution with any longevity. Tree out.