Exactly. Holdover does not have a contractual agreement with OP, landlord does. Holdover has no DUTY to OP and OP cannot sue him for breech of a duty that does not exist. On the other hand, LL's duties are EXPLICITLY spelled out in the contract. Duties were breeched, resulting in damages to OP. Therefore, LL is liable to OP, and holdover is liable to LL, who holdover has a contractual agreement with.
I'll explain this real slowly for Johnd...tort law 101.
1. One party has an established duty to the other.
2. That party has breeched the duty through negligence or maliciousness.
3. That breech in duty directly led to monetary damages.
The only element that might be questionable is negligence, but at least IMO, from the facts that have been presented, the LL was negligent in his representation of the property as available when he was fully aware he was going to need a court order (which he did not yet have nor had filed the court action to obtain) in order to get the holdover out. Which is the element that the landlords on this board seem to be ignoring. The holdover was not a SURPRISE to this landlord, he wasn't blindsided or caught unawares. He KNEW the guy had already refused to leave and would continue to do so until the sheriff physically threw him out. Yet he continued to represent the property as "available" or "available any day now", right up until moving day. Had he even attempted to let OP know a few days beforehand so she could have remained at her old place and not incurred so many expenses, that might have been sufficient to get him off the hook, but he didn't even do that. And that makes him liable.
And I don't get why you think a holdover tenant is beyond the landlord's control anyway. You all know exactly how to get a holdover out of your building and how long it will take to do it. You could tell your prospective tenant, I filed the UD on this date, the hearing is on this date, I should have the order of posession by around this date, and you should be able to move in by X at the latest. Had this LL done that, that might have exempted him from negligence. But he didn't. In fact he TOLD OP that he'd gotten an eviction when he hadn't even filed one, I suspect that this LL was clueless enough to think that a 30 day notice expiring was enough for him to be able to get the sheriff involved.
OK I'm done now, my head hurts from beating it against this wall.