As in most languages, spoken English is more informal than the prescribed form that is set out. Especially with the Germanic languages, which tend to have quite strict grammar patterns compared to Slavic languages, people look for a way around. This morning I had a debate with myself over what was the correct form; "did you use to?" or "did you used to?" (it's the first one that is correct, but it sounds somewhat unnatural). Native speakers aren't infallible, and some written language, especially if it is conveyed from the point of view of a narrator, will try to replicate this grammatical ease-of-use which we tend to choose in day-to-day speech.

Here "the works" is an idiomatic expression meaning "everything", to be specific they had every parasite such as lice, fleas, ticks ...and every problem you can imagine - this sort of over-statement is grammatically known as "hyperbole", clearer in such statements as "He has had thousands of girl friends". Work is uncountable, as you say, but is occasionally used in the plural: The Ministry of WORKS. The language might follow the grammar, but sometimes the people do something different! All grammar is a description of what people say and write - or somebody's idea of what they should say. This means what is actually said may not always correspond to what grammar books say they should say!

the works = everything It is a distinct expression, and doesn't break any grammatical rules. Contrary to popular belief, spoken English adheres strictly to its grammatical rules. The example you gave above is a typical one of misunderstanding. You simply misunderstood the word for something else. That happens a lot, especially with ESL teachers whose understanding of the language is very limited.

Many authors prefer using a more casual grammatical style, that which is more consistent with conversation of the period, or reflective of the current culture. However, your example is related to the usage of conversational slang, not grammatical structure. In your example, "the works" is actually an old slang term. It basically means "everything possible", or "every possible option". Common usage: "Give me a sandwich with "the works" (every vegetable, condiment, and topping available)." The example: "When Wayan first found Big and Little Ketut,they hadn't eaten for days, had lice and parasites, the works". "When Wayan first found Big and Little Ketut,they hadn't eaten for days, had lice and parasites, (every bad thing that could have possibly happened to them)".

"The works" is somewhat of an expression in English. It is a little uniqueMost uncountable nouns can still be plural. Water can be waters. Waters would mean different collections of water such as different rivers. Where I live we usually completely ignore proper English, but there are some things that are never done wrong. The word "whom" is not the same as who, but I never hear people say whom. Y'all isn't proper, but I didn't know that for a long time. I didn't know the word you can be plural. We have our conventions based on region. It isn't proper to end a sentence with a preposition, but people still do. In fact sentences can become akward if you don't