Unfortunately I don't think the lack of shower or time or strength of the relationship says anything at all.
As an "Ok looking single woman", the behaviour of lots of "nice married men" in the workplace in terms of "fishing around for options" is appalling.
If they hear a woman has had a relationship breakdown and/or is vaguely available and there's ANY small chance of engineering something and getting their dick wet, ..they're in there. They'll go for everyone until they get a hit. Numbers game.
The "had a mutual dating situation with a mature student after marriage ended" story sounds like a cover for "I target everyone, and this is just in case you hear about the story from someone else".
And they don't give a damn what their colleagues think (or their colleagues will cover for them. Or they don't care if there's gossip as it reflects negatively on the woman, not them).
and yes, these guys talk about their kids, and clearly would have a lot to lose financially if their marriage broke down...It doesn't matter.
They don't have to be in love with the woman, or her to be a great beauty or have any special time together....just have the opportunity and time.
They're not wandering around like Hugh Hefner with Playboy vibes. Many of them are geeky and work focussed.
And yes, a clinch on a Friday morning might be something they scheduled in.