In my humble opinion, I think it’s two seperate things.
It’s definitely up the the rav hamachshir if he doesn’t want to
give his Hechsher to a place that has waitresses dressed inappropriately.
Especially a more respected hechsher.
However, I think that it has nothing to do with the kashrus of the food.
(rather the place)
The hechsher should let it be known publicly that
it is only on the food & not the atmosphere.
Just like the caterers write that the booze & alcohol
at certain simchas is not included in their hechsher.
I think there should be two seperate ratings systems.
1)kashrus of the food.
2)Kashrus of the atmosphere.
Like this Ehrliche people would be forewarned
not to go eat out (alone or with family)
where they dont feel comfortable.
The young wild ones of our generation who are still eating
kosher, but not on the level, should not be deprived of a hechsher.