As is normal, I’ve made a typo somewhere. Not enough to get a syntax error, but I get no names in the HUD and I get an null instance error. At least that gives me an idea where to go looking. I probably fat fingered something or gave a different class name than I wanted to give.
Let the hunt begin, again.
Not to bad of a hunt this time. Runtime error got me to this line in Leaderboard.cs:
LeaderboardEntityDisplay leaderboardEntity = Instantiate(leaderboardEntityPrefab, leaderboardEntityHolder);
Turns out I didn’t populate my [SerfializeField] leaderboardEntityPrefab for this script. Now things are working again.
Well done for finding it. 
Sometimes just writing it out can help our brains work through the problem and find the issue – this is a real debugging technique! (see “rubber duck debugging” 
)
Along with Rubber Ducking it (yes, I am quite familar with that) I am hoping others will learn from my mistakes as long as they stay near the top.
Need to find error #2. Only the first one in gets on the leader board. And as I suspected, when I kill that guy, he drops off the board as well. Most likely a != where the should be an == (or worse a = where it should be an ==). If only C# would learn from powershell and use -eq instead of ==. I will make less mistakes.