I’d rather get fired and collect unemployment than the tawdry severance. If they just suddenly give you a warning letter, you could claim that you got no previous complaints about your work, then WHAM! OLCC? Nope. Job performance improvement letter? Nope. Just the final step in the hierarchy, a warning letter. Their lack of documentation would be why they lose any appeal.
The only thorn I put in mgt’s side is the trouble I have getting a LEO to open drop boxes. Sometimes both methods work. Sometimes just one. Often, nothing works except the code. I’m told that no one else has this happen. But my mgr has come out, seen me use the correct procedures and saw the box not open.