It represents the employee signing-off on an altered legal document. In other words, if you sign, it's "OK", because you agreed to the changes. You've probably just lost your right to challenge the alterations.
This is nothing new. FedEx managers have been altering timecards and reports for years. When I was a "lead" and considering management, one of the first things I was taught was how to make everything "100%". I refused to participate, and dropped out of the program.
If you take a management position at FedEx, you must be willing to falsify and to do whatever the company asks regarding cheating employees out of compensation. Like the break instead of Code 43 garbage here. Late CTVs and planes are Fred's problem, not yours. FedEx, in it's infinite cheapness, is trying to steal (again) from the gullible. A lot of Purple Sheep People will just sign it in order to not be on the blacklist.
This is the kind of kind of activity that will eventually result in a large class action. I'm sure Dano has never falsified or otherwise compromised his integrity as a "manager".