Relief flooded him when he knew Jessica was alive. No one told him anything for hours while he laid in a hospital bed.
He'd failed to keep Adam Clay away, he'd failed to keep Derek safe. His death was no great loss to him, but Jessica, he knew, would be devastated.
That was her weakness. That no good son of hers. Wallace's was her. She got her claws into when her husband had been alive. Ever since long even after they crashed and burned he cared for her.
Enough that he's ended up in this hospital bed, enough that when she comes to him looking for revenge, she will sooner or later. He'll help.