Fruiting bodies at the base of a mature White Oak

[uglypageant]

Background info:
88cm dbh white oak, Southern Ontario. 60-70% of the canopy looks to have scorched leaves and possibly chlorotic, but it may have been the way the sun was hitting them. The scorching seems to be mostly in the middle of the trees, from a top down perspective. I'm still collecting some info from the homeowner, but it looks like paving stones were installed around a pool, and they had to drive equipment within 1m of the oak to get to the pool.

All around the base of the tree there look to be the fruiting bodies of dead man's fingers, but something seems to be a bit off which makes me wonder if they're a different species of a Xylaria fungus. They are still white, but I thought that might be an immature state before they become black. The fruiting bodies are present all around the circumference of the base. On one side of the tree they extend approximately 1' up the trunk. My concern is that if Xylaria is a saprophyte (terminology?), the tissue at the base of the tree or roots may be dead or damaged.

Wondering if anyone has seen something similar or can point me in the right direction for identification.

 

[Raintree]

Looks like Xylaria to me this would go hand in hand with the chlorosis. Very serious issue, need to be certain, removal is the only option.
Just want to add, I've only seen Xylaria in the woods. Never came across it in the urban environment.