I know of a lower ranked person who got one of these payouts.
She was constantly off sick with made up health problems (I know this, we were friends til she decided I'd betrayed her by having my own issues to handle). Mostly she used poor mental health as the reason but also some physical things with very little evidence, but that don't necessarily have a lot of medical evidence.
Whenever a sick review was done she would threaten ACAS, the union, claim she was being treated unfairly and differently to others (she wasn't).
She would make a fuss every time annual leave was brought up as she always wanted to be off at the busiest leave times (i.e. Christmas) and as there needed to be staff in wasn't always allowed it. I know she wasn't given any less than others but she claimed she was.
We had to work "shifts" to ensure phone cover, and because one other staff members contracted hours predated this arrangement and therefore she didn't have to change them (and actually, she offered to do one of the days no one else wanted to as it suited her, when she could have done none), this woman complained that it was unfair to her that someone else's contract said differently.
In the end they offered her a settlement to allow her to stop working (which is what she wanted) for a year, meaning she had time to sort out something else. But it was essentially so she'd go away.