Since having him there on Christmas Eve is something you'd be doing for your D, perhaps ask her what she'd prefer? She might not welcome the discomfort of a strained Christmas with an alien-eyed father.
If she really wants him there, that could be your "gift" to her. However, you ask "Would it be good for D&H?" and that's not really your issue to worry about--it's completely his. It seems like trying to "fix" their relationship while putting your own needs last.
If your daughter doesn't care either way, I'd be tempted not to invite him, to let him really feel what kind of future he's setting up for himself.
