A manager propositioning subordinates is essentially always wrong.
Even in some unlikely situation where the subordinate had unambiguously and clearly been signalling sexual interest in the manager, over a sustained period of time, the manager would be _very_ ill-advised to enter into non-professional relations while the employee was a subordinate or the employee's career could in any way be perceived to be influenceable by the manager. The manager should just not go there, full stop.
In this specific case, she'd been there one day, so we can rule out that highly unlikely scenario, and conclude that if such a proposition was made it was clear misconduct.
Mature, large companies (least, that I'm familiar with) have fairly strict rules banning relations between managers and subordinates for very good reason. Precisely because such relations are very likely to be unhealthy and improper: For the manager, for the subordinate, for other subordinates of the manager, and for the company.