I'm trying to confirm this..
That YT account is a legit railfan. Any question about how he happened to be in the right spot at the right time is because it's a true railfan. There's long stretches of rail where they can film it passing and stay in front of it for the next spot.
This doesn't look like a combat unit. Lots of backhoes and loaders, trucks and trailers.
There's live cams for trains. I'm trying to find it, or a report of this train. I'm not a trainfag though.