Well, after hours of fruitlessly trying to solve the problem in some clean way, I eventually dirty hacked my way around it. Ironically, the “clean” solution required touching six files, the “diry” solution required touching 2 lines. I don’t like it from a logical perspective but the extra burden it imposes on customers is minimal and would require them to have non-default settings to even notice, so I guess that is survivable. (I also checked and out of 560 word lists it affects only 8 of them.)
I think I’ll chalk this one up to “Eh, sometimes you just have to ship it.”
Now to pay my penance for slackadaisical testing earlier: new CDs for six people, who each got one with the bug on it.