None of the cabinets on that exchange were done with just commercial money, six are part of the Kent BDUK project and the other four are the smaller ones, i.e. your cab looks to be smaller, so in terms of value for money it lost out compared to some others.
Yours is probably the next one on the list if they do another in the area.
So if you want to campaign it is the combination of planners at council and BT. Ball park cabinet costs vary between £30,000 to £50,000 and a big variable can be the cost of power.
The problem is that the project has limited funding, and there may be other cabs with 200 premises that can be enabled and not yours.