Yikes! What did you do?
I invited the inspectors in and excitedly showed them all the features of the treehouse and how the kids love it so I could establish some rapport with them. And then we talked about why the neighbors reported it; it wouldn't have been for the extra 2 feet. I showed them how the treehouse was not even visible to any neighbors but the one next door, it was too tucked in the redwoods and our house backs up to a canal.
I know the next door neighbors well and which of them was likely to have reported it, and paid a friendly visit. We do them a lot of favors like picking up their mail when they're gone.
Luckily we never heard anything else from the inspectors or the neighbors and it has been 5ish years. Shortening it would have been hard and there was no gain in it for our neighbors.