” That he did in fact inquire, indicates he cares deeply enough about it”
It’s actually more likely that he has reason to believe that she doesn’t dress tzanua and he wanted to know if its true. A greasy boy would never ask because he knows no one would set him up with a girl who even dressed borderline.
As an aside she may be trying to dress tzanua which is something that Gefen could say, but it is unlikely that she would want to marry someone who won’t let her dress as she wants. Personally I would say exactly as it is. ‘Depends on your standards. Sometimes her knees are showing and sometimes her skirts are tight.’ It’s not lashon hara to describe how she dressed in public but its not your place to say she’s not dressed halachic when you don’t know all the leniencies involved.