Failed to process placeholder <caster.tt.top> in xPlaceholderString{'<caster.tt.top>'}

Summary

When trying to use in-line conditions for a targeter, I am getting a null.

Steps to reproduce

Mob:

Incendius:
  Type: SKELETON
  Display: '&5&lIncendius'
  Health: 20
  Damage: 8
  Options:
    AlwaysShowName: true
    PreventOtherDrops: true
    PreventItemPickup: true
  Skills:
  - skill{s=Lava-Ejection-Start} @self

Skills:

Lava-Ejection-Start:
  Skills:
  - skill{s=Lava-Ejection-Drop} @PlayersInRadius{r=40;conditions = [  - stringEquals{val1=<caster.tt.top>;val2=<target.name>} false]}
Lava-Ejection-Drop:
  Skills:
  - totem{oS=Lava-Ejection-Totem-Start;onTick=Lava-Ejection-Tick;i=6;md=120;yOffset=0.0;oE=Lava-Ejection-Soak} @RLNTE{a=1;r=12;s=3;target=casterspawnlocation;}

Current behavior

Null on caster

Intended correct behavior

I am expecting the PIR to ignore the player with the highest threat, but the caster seems to be null in the context of the inline condition.

Server log file

https://pastebin.com/0rqXGyFX

Debug log snippet

https://pastebin.com/k5bB27eQ

**Proposed fixes

Describe what you think the issue or any potential fixes may be.

Version 4505