Need explanation on why dual conditions on a treason plot

[HamsterStomp]

Ruling as a petty king, my bishops (who are vassals but aren't counting towards my vassal limit, but that's another issue) have fabricate treason plots available in the drop down intrigue menu. However there are 2 sets of conditions, one valid one invalid.

No additional mods running
Current Game Version 2.8.3.4
Current Mod 4.07.8
Current Patch 2.8.3.4
Check Sum XFMO

 

[Ictivion]

Not a dev, but looking at those requirements, the one that is greyed out is to plot against a fellow vassal, and the one isn't greyed out is for a vassal of your own.
Basically, if you were both Count+ vassals of the same Duke/King/Emperor, you could use the one that is greyed out, but instead since you're the liege of this baron and count, you need to use the other one.

I'm guessing the oversight (if you can even call it that) is in the "potential" clause of these plots which is an otherwise invisible requirement that only exists in the background to determine whether the option even shows up for you in-game or not.