Yes, he could harass women as a custodian. I think they need to make sure the locks on the women's restrooms are in good working order, and not let anybody in while he's scrubbing the toilets.

However, it's a lot easier for him to abuse his power and victims if he's in management. I work for the USPS. Virtually ALL sexual harassment cases in the USPS had a manager and subordinate employee involved in a "Quid Pro Quo"  or something-for-something situation where the manager either made promises to promote the subordinate or promised not to demote or terminate them in exchange for sexual favors.

Years ago, there seemed to be a plague of managers who thought the workplace and subordinates were ripe for the picking. The USPS paid out millions to victims as a result. Some of these victims lives were ruined from the experience, and some committed suicide. For this, the USPS was supposed to implement a zero-tolerance policy towards offenders and remove them. I guess things haven't changed.