Yes, he does regenerate, quite fast, such that arrows are a waste of time and materials.

Did you see this one? I just watched it yesterday. Some of it is cheese, but if that's what it takes, short of using the console...

https://www.youtube.com/watch?v=L2nt22yd064

The last time I killed him, I used a herd of lox to get him down to about a third, then bonemass tanked the rest. Still died once. It seems like wolves work much better because they can pile on better to attack.

I think the real trick is whether you can actually move or not. Those meteors do stun and those were what kept getting me. If you can get out of the way before the meteors hit you then that seems to make all the difference. If you're slow, then no dice. (I rather liked the part in the video above where the wet debuff makes it so you can block those normally, but that strategy depends a lot on location.)

After that, I watched this guy's Queen videos, and I am not at all interested in doing that fight now.