Your friend is working for a place where he cannot finish his work in the required hours and is not supposed to leave till it is done or threatened with firing if he doesn't get his work done?
It is never a good idea to work overtime off the clock. For starters, it's dumb to donate your free time to this employer. Even if he does, the Wage and Hour investigator could come back on this employer and force them to pay him for the work. This could cause them to fire him too. They fully understand the legalities of this, that if he is not on the clock and something happens, the company is not covered legally. For example if he were injured on the job but off the clock, it would be very bad for the employer. Worker's comp would still apply to him, also.
He needs to do as much as he can do on the clock. Then he needs to tell the supervisor that he was unable to finish the work. He needs to ask the supervisor if they want him to work overtime to complete it. If they say no, that no one is authorized to do overtime, he informs them of the situation as it is, how much is undone. Then he goes home, with the work undone. If they want to fire him, they will be able to do so, but he is likely to be approved for unemployment insurance, which will cost the employer money, because they have fired him without a good misconduct reason.
If he is caught working unauthorized overtime, even without pay, the company can fire him and he would have a much less chance of being approved for unemployment, because he knew and had been told he was not supposed to do this.
It is easy for a company to assign more work than a person can do during their allotted work hours. If he is sneaking around and doing the work off the clock to get it done, this keeps management from realizing they either need to hire more staff or change the workload. There is always going to be more work than he can get done if he starts donating his time for free.
Many people take too much responsibility, they genuinely want to do a good job, and call it "their" work, or their share or their assignment. But really it is not theirs, it is work that the employer needs done. It is the supervisor's responsibility to see that the work is done. If the employees cannot do the work in the time allotted, they will need to change the way they are distributing the work, not threaten the staff with firing.
This concept, of asking the staff to do more and more in their work hours without giving them more time or more help, is called asking them to "spin straw into gold." You can demand all day, but if the employees cannot legitimately work and try their best and get the job done, then they are not considered to be at fault for not spinning their straw into gold, doing the impossible.
And if they are there on the premises doing the job, they are considered by the federal wage laws to be working at the job, whether or not they have chosen to clock themselves out or report their time or not.
And then he very well may be fired for it. Because if anyone complains, the federal Wage and Hour division, (since Florida does not have a state agency that works with this) may come in and force them to pay this overtime, even though it has not been reported. And working "unauthorized overtime" is a much worse reason to be fired than not being able to get your work done when you are doing your best.
