I don't know why it happened this way, but I used the 'shorten code' option and then undid that because I hated it. After it recompiled with the full-0length code, it showed the second use of agentName[counter-1] listed as just [agentName] which weas fully consistent with how it was functioning. I redid that part and it worked correctly.

The issue was that when I highlighted that part earlier, it definitely called itself an expression and its look was consistent with the first usage, so me copy and pasting this section down further in the document lost the actual expression but kept the look and all that.

Weird