The classic solution to lowballing is to get a higher paying counter offer (ideally more than 1) and be in the position of decision-making.
You can then share your concerns with CityMall without sharing your counter offers to see their genuine reaction to the situation. If it isn't good enough, you can explore the counter offers.
Why not use your counter offer to trigger retention discussions? Because it practically makes the work environment toxic and gets you labelled as a "flight risk" in the eyes of your management.
This is what I've done before and went with the counter offer.