[AndyTheBear]

If this really is how it went down, what would give them the idea it was someone other than housekeeping?

I am not sure, but there are plausible scenarios I could imagine: Maybe there was a do not disturb hanger on door. Maybe they already talked to the hotel and were able to eliminate that possibility but the reporter was not aware of that. Until we know we can only speculate.

[9YearLurker]

Yes, we can only speculate. But from the record of these events over the last couple of decades, the odds are that the “victim” was the perpetrator.