The two are not exactly correlated, need more information if you want help.
Seems like when Charlotte needs 20k for a boobjob (and is still in debt) then you buy the photo studio for 25k, she doesn't come back anymore for jobs. She also doesn't return after the debt is paid off either and haven't got her to 20k (for the boobjob) yet so not sure if she returns after that because it doesn't allow you to lend her the money like it does with Stella so it's a huge grind if you don't want to cheat. (It took about 20 mins of skipping the days to get Charlotte out of debt and is going to take hour/s for her to make 20k alone)
Money seems to be the biggest issue in the game personally. It just takes ages to get enough or the price of things is way too high so you're sitting there going to work and BLC meetings for money towards the end. Easy fix would be to look at prices again or allow the player to get promotions at his job. (Maybe could turn his boss into a bimbo or something and get more hours/money) which would add more content/another character and more money.
Attached a save file (game version 6.1.1) with the current issue. I have the photo studio, she is out of debt, doesn't have 20k for the boobjob and never comes for jobs anymore. (Not sure if it just hasn't been implemented yet)