Job is forcing employees to pay out of pocket for register shortages

Location: South Florida
I started working in a franchised own thrift shop and the owner is accusing all of the staff from stealing from the register.

Since i started working there 3 weeks ago i’ve noticed all of their operational procedures ARE TERRIBLE. Imagine there’s 20 different tasks and 8 different managers and they all have a different way of doing something.
That’s 160 different ways of completing tasks so simple like securing an alarm tag on merchandise. And if you don’t do a task the way your specific opening/closing manager doesn’t like, it’s wrong. Do it over. Huge paragraph in a Whatsapp group chat (that gets spammed every 30 seconds with messages from the owner).

So you get the gist of how dysfunctional this company is. The register (multiple people use this register for various things, money transfers, checking out, more than 3 people use one register daily.) has been short or over almost every night since i’ve started and i know this because it’s all on display in the group chat of everyone trying to understand why, it’s short/over. They’ve decided that a “good” system is to count the 5 registers maybe 10 times daily at random times to check for discrepancies.

Anyways, the owner was apparently watching me through the cameras yesterday saying I count the money “incorrectly” because i don’t do it the way she does. I’ve been in retail for 4+ years of all positions and have never gotten criticized of how i count, only praised and have never lost money or misplaced while counting, etc. This is a message sent very early in the morning so i don’t see it until later so i just never respond because there was 200+ messages that came after anyways. She’s accusing everyone in the store of stealing and saying we can’t bring purses or backpacks to work anymore. (the only place i’ve worked for that doesn’t do bag checks, by the way) and that whoever is stealing will be “walking out in handcuffs soon”. This is after she sent the message about me counting the money. I discovered a ten dollar shortage that night which erected this mess. She stated next time it is short we will have to pay out of pocket. One night it was short more than 300 dollars. Which i cannot afford to pay out of pocket at the current financial state i am in.

In Florida, can an employer force employees to pay a large shortage like that? Without exact, physical proof? When multiple people use the same register? I know there’s a law that has to do something about minimum wage but i can’t find a clear answer anywhere online so a link or something to a direct clear answer will be nice to calm my worries.

PS: i’ve already found a better job, just waiting to fully commit and get paid a bit first.