It seems so far fetched to me!
T itself is definitely not caused by the tree, but the thought that the lights might have a (minor) exacerbating effect does not sound completely strange, at least not to me. Since my onset of T, there have been a few devices that were capable of giving a boost to my sounds, for example the smart meter below the stairs in my house. During the month that my T was lowering the quickest, I've had one week where I could actually "hear" the ceiling lights at work: the sound faded if I went off to get a drink away from them, and returned as soon as I entered the area with the lights again. I experimented quite a bit with this odd phenomenom, but it disappeared in the next week.
My own theory is that certain frequencies caused some kind of vibration in my tensed up neck muscles, which at some point gets picked up by the auditory systems in the brain, magnifying real sounds in the process. This thought is mostly based on studies
like this one, where connections are found with muscles concerning somatosensory T. Just like a highly strained piece of twine will respond to the slightest touch and keep vibrating for a long time, a tense muscle might do the same when exposes to external frequencies. When the muscle gets stretched over time, the required frequencies for resonance change, less (buildup of) vibration will occur, and the sound increase during exposure will go down. This explanation would match my experience during that time.
Still, quite likely it is just a coincidence. There is an easy way to check though: turn off the tree lights for a few evenings and check your T intensity. If you're sure that it's lower, then turn the lights back on, and see if it increases again. However, keep in mind that such an experiment is hard to look at in an objective way, unless the difference in T is high.
And for the record: even if it is the tree, I'm quite sure it doesn't give any permanent damage. This effect purely acts as a catalyst, at least that's how it behaved for me