I’m not sure about Greys in particular, but years ago, another lifetime actually, I worked in an office building. They put up some power lines a year after I was there, and birds started to crash into the windows.
Did a little research at the time, and power lines generate magnetic fields.
Some birds, maybe all birds navigate using the earth’s magnetic poles during migration.
Some research has shown a mild causality between power lines and brain cancer in humans. Proved up or not, real estate next to power lines tend to be less expensive. They even have done studies about cell phones and cancer. Who knows 🤗
Might be worth some updated research if you can’t find a cause. Last time I looked was over 30 years ago. That was before google lol
An easy way to check the pole you’re talking about would be to get a plain old compass and walk around it. If it’s active the compass will be erratic if it’s putting off anything.